diff --git a/event/adapter/eventtest/eventtest.go b/event/adapter/eventtest/eventtest.go
index c3f9137..8c1cdce 100644
--- a/event/adapter/eventtest/eventtest.go
+++ b/event/adapter/eventtest/eventtest.go
@@ -58,7 +58,7 @@
 }
 
 var InitialTime = func() time.Time {
-	t, _ := time.Parse(time.RFC3339Nano, "2020-03-05T14:27:48Z")
+	t, _ := time.Parse(logfmt.TimeFormat, "2020/03/05 14:27:48")
 	return t
 }()
 
diff --git a/event/adapter/gokit/bench_test.go b/event/adapter/gokit/bench_test.go
new file mode 100644
index 0000000..7d2fb3e
--- /dev/null
+++ b/event/adapter/gokit/bench_test.go
@@ -0,0 +1,72 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package gokit_test
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"testing"
+
+	"github.com/go-kit/kit/log"
+	"golang.org/x/exp/event/adapter/eventtest"
+	"golang.org/x/exp/event/adapter/logfmt"
+	"golang.org/x/exp/event/bench"
+)
+
+var (
+	gokitLog = bench.Hooks{
+		AStart: func(ctx context.Context, a int) context.Context {
+			gokitCtx(ctx).Log(bench.A.Name, a, "msg", bench.A.Msg)
+			return ctx
+		},
+		AEnd: func(ctx context.Context) {},
+		BStart: func(ctx context.Context, b string) context.Context {
+			gokitCtx(ctx).Log(bench.B.Name, b, "msg", bench.B.Msg)
+			return ctx
+		},
+		BEnd: func(ctx context.Context) {},
+	}
+	gokitLogf = bench.Hooks{
+		AStart: func(ctx context.Context, a int) context.Context {
+			gokitCtx(ctx).Log("msg", fmt.Sprintf(bench.A.Msgf, a))
+			return ctx
+		},
+		AEnd: func(ctx context.Context) {},
+		BStart: func(ctx context.Context, b string) context.Context {
+			gokitCtx(ctx).Log("msg", fmt.Sprintf(bench.B.Msgf, b))
+			return ctx
+		},
+		BEnd: func(ctx context.Context) {},
+	}
+)
+
+type gokitKey struct{}
+
+func gokitCtx(ctx context.Context) log.Logger {
+	return ctx.Value(gokitKey{}).(log.Logger)
+}
+
+func gokitPrint(w io.Writer) context.Context {
+	logger := log.NewLogfmtLogger(log.NewSyncWriter(w))
+	now := eventtest.ExporterOptions().Now
+	logger = log.With(logger, "time", log.TimestampFormat(now, logfmt.TimeFormat), "level", "info")
+	return context.WithValue(context.Background(), gokitKey{}, logger)
+}
+
+func BenchmarkGokitLogDiscard(b *testing.B) {
+	bench.RunBenchmark(b, gokitPrint(io.Discard), gokitLog)
+}
+
+func BenchmarkGokitLogfDiscard(b *testing.B) {
+	bench.RunBenchmark(b, gokitPrint(io.Discard), gokitLogf)
+}
+
+func TestGokitLogfDiscard(t *testing.T) {
+	bench.TestBenchmark(t, gokitPrint, gokitLogf, bench.LogfOutput)
+}
+func TestLogGokit(t *testing.T) {
+	bench.TestBenchmark(t, gokitPrint, gokitLog, bench.LogfmtOutput)
+}
diff --git a/event/adapter/logfmt/logfmt.go b/event/adapter/logfmt/logfmt.go
index 71aaa49..83102e4 100644
--- a/event/adapter/logfmt/logfmt.go
+++ b/event/adapter/logfmt/logfmt.go
@@ -9,6 +9,8 @@
 	"fmt"
 	"io"
 	"strconv"
+	"unicode"
+	"unicode/utf8"
 
 	"golang.org/x/exp/event"
 )
@@ -16,6 +18,8 @@
 //TODO: some actual research into what this arbritray optimization number should be
 const bufCap = 50
 
+const TimeFormat = "2006/01/02 15:04:05"
+
 type Printer struct {
 	buf     [bufCap]byte
 	needSep bool
@@ -54,10 +58,9 @@
 }
 
 func (p *Printer) Event(w io.Writer, ev *event.Event) {
-	const timeFormat = "2006-01-02T15:04:05"
 	p.needSep = false
 	if !ev.At.IsZero() {
-		p.label(w, "time", event.BytesOf(ev.At.AppendFormat(p.buf[:0], timeFormat)))
+		p.label(w, "time", event.BytesOf(ev.At.AppendFormat(p.buf[:0], TimeFormat)))
 	}
 
 	if ev.Parent != 0 {
@@ -101,30 +104,24 @@
 }
 
 func (p *Printer) Ident(w io.Writer, s string) {
-	//TODO: this should also escape = if it occurs in an ident?
 	p.Quote(w, s)
 }
 
 func (p *Printer) Quote(w io.Writer, s string) {
-	if s == "" {
-		io.WriteString(w, `""`)
-		return
-	}
-	if !needQuote(s) {
+	if !stringNeedQuote(s) {
 		io.WriteString(w, s)
 		return
 	}
-	// string needs quoting
 	io.WriteString(w, `"`)
 	written := 0
-	for o, r := range s {
+	for offset, r := range s {
 		q := quoteRune(r)
 		if len(q) == 0 {
 			continue
 		}
 		// write out any prefix
-		io.WriteString(w, s[written:o])
-		written = o + 1 // we can plus 1 because all runes we escape are ascii
+		io.WriteString(w, s[written:offset])
+		written = offset + utf8.RuneLen(r)
 		// and write out the quoted rune
 		io.WriteString(w, q)
 	}
@@ -134,8 +131,27 @@
 
 // Bytes writes a byte array in string form to the printer.
 func (p *Printer) Bytes(w io.Writer, buf []byte) {
-	//TODO: non asci chars need escaping
-	w.Write(buf)
+	if !bytesNeedQuote(buf) {
+		w.Write(buf)
+		return
+	}
+	io.WriteString(w, `"`)
+	written := 0
+	for offset := 0; offset < len(buf); {
+		r, size := utf8.DecodeRune(buf[offset:])
+		offset += size
+		q := quoteRune(r)
+		if len(q) == 0 {
+			continue
+		}
+		// write out any prefix
+		w.Write(buf[written : offset-size])
+		written = offset
+		// and write out the quoted rune
+		io.WriteString(w, q)
+	}
+	w.Write(buf[written:])
+	io.WriteString(w, `"`)
 }
 
 func (p *Printer) label(w io.Writer, name string, value event.Value) {
@@ -153,21 +169,37 @@
 	}
 }
 
-func needQuote(s string) bool {
+func stringNeedQuote(s string) bool {
+	if len(s) == 0 {
+		return true
+	}
 	for _, r := range s {
-		if len(quoteRune(r)) > 0 {
+		if runeForcesQuote(r) {
 			return true
 		}
 	}
 	return false
 }
 
+func bytesNeedQuote(buf []byte) bool {
+	for offset := 0; offset < len(buf); {
+		r, size := utf8.DecodeRune(buf[offset:])
+		offset += size
+		if runeForcesQuote(r) {
+			return true
+		}
+	}
+	return false
+}
+
+func runeForcesQuote(r rune) bool {
+	return !unicode.IsLetter(r) && !unicode.IsNumber(r)
+}
+
 func quoteRune(r rune) string {
 	switch r {
 	case '"':
 		return `\"`
-	case ' ':
-		return ` ` // does not change but forces quoting
 	case '\n':
 		return `\n`
 	case '\\':
diff --git a/event/adapter/logrus/bench_test.go b/event/adapter/logrus/bench_test.go
index 51eb0ee..ce741ff 100644
--- a/event/adapter/logrus/bench_test.go
+++ b/event/adapter/logrus/bench_test.go
@@ -84,22 +84,5 @@
 }
 
 func TestLogrusf(t *testing.T) {
-	bench.TestBenchmark(t, logrusPrint, logrusLogf, `
-time="2020/03/05 14:27:48" level=info msg="a where A=0"
-time="2020/03/05 14:27:49" level=info msg="b where B=\"A value\""
-time="2020/03/05 14:27:50" level=info msg="a where A=1"
-time="2020/03/05 14:27:51" level=info msg="b where B=\"Some other value\""
-time="2020/03/05 14:27:52" level=info msg="a where A=22"
-time="2020/03/05 14:27:53" level=info msg="b where B=\"Some other value\""
-time="2020/03/05 14:27:54" level=info msg="a where A=333"
-time="2020/03/05 14:27:55" level=info msg="b where B=\"\""
-time="2020/03/05 14:27:56" level=info msg="a where A=4444"
-time="2020/03/05 14:27:57" level=info msg="b where B=\"prime count of values\""
-time="2020/03/05 14:27:58" level=info msg="a where A=55555"
-time="2020/03/05 14:27:59" level=info msg="b where B=\"V\""
-time="2020/03/05 14:28:00" level=info msg="a where A=666666"
-time="2020/03/05 14:28:01" level=info msg="b where B=\"A value\""
-time="2020/03/05 14:28:02" level=info msg="a where A=7777777"
-time="2020/03/05 14:28:03" level=info msg="b where B=\"A value\""
-`)
+	bench.TestBenchmark(t, logrusPrint, logrusLogf, bench.LogfOutput)
 }
diff --git a/event/adapter/zap/bench_test.go b/event/adapter/zap/bench_test.go
index bbad9c8..85b8050 100644
--- a/event/adapter/zap/bench_test.go
+++ b/event/adapter/zap/bench_test.go
@@ -54,7 +54,7 @@
 	ec := zap.NewProductionEncoderConfig()
 	ec.EncodeDuration = zapcore.NanosDurationEncoder
 	timeEncoder := zapcore.TimeEncoderOfLayout(bench.TimeFormat)
-	ec.EncodeTime = func(t time.Time, a zapcore.PrimitiveArrayEncoder) {
+	ec.EncodeTime = func(_ time.Time, a zapcore.PrimitiveArrayEncoder) {
 		timeEncoder(now(), a)
 	}
 	enc := zapcore.NewConsoleEncoder(ec)
@@ -83,7 +83,7 @@
 2020/03/05 14:27:52	info	a where A=22
 2020/03/05 14:27:53	info	b where B="Some other value"
 2020/03/05 14:27:54	info	a where A=333
-2020/03/05 14:27:55	info	b where B=""
+2020/03/05 14:27:55	info	b where B=" "
 2020/03/05 14:27:56	info	a where A=4444
 2020/03/05 14:27:57	info	b where B="prime count of values"
 2020/03/05 14:27:58	info	a where A=55555
@@ -103,7 +103,7 @@
 2020/03/05 14:27:52	info	a	{"A": 22}
 2020/03/05 14:27:53	info	b	{"B": "Some other value"}
 2020/03/05 14:27:54	info	a	{"A": 333}
-2020/03/05 14:27:55	info	b	{"B": ""}
+2020/03/05 14:27:55	info	b	{"B": " "}
 2020/03/05 14:27:56	info	a	{"A": 4444}
 2020/03/05 14:27:57	info	b	{"B": "prime count of values"}
 2020/03/05 14:27:58	info	a	{"A": 55555}
diff --git a/event/adapter/zerolog/bench_test.go b/event/adapter/zerolog/bench_test.go
index 822100f..3c49770 100644
--- a/event/adapter/zerolog/bench_test.go
+++ b/event/adapter/zerolog/bench_test.go
@@ -66,7 +66,7 @@
 {"level":"info","time":"2020/03/05 14:27:52","message":"a where A=22"}
 {"level":"info","time":"2020/03/05 14:27:53","message":"b where B=\"Some other value\""}
 {"level":"info","time":"2020/03/05 14:27:54","message":"a where A=333"}
-{"level":"info","time":"2020/03/05 14:27:55","message":"b where B=\"\""}
+{"level":"info","time":"2020/03/05 14:27:55","message":"b where B=\" \""}
 {"level":"info","time":"2020/03/05 14:27:56","message":"a where A=4444"}
 {"level":"info","time":"2020/03/05 14:27:57","message":"b where B=\"prime count of values\""}
 {"level":"info","time":"2020/03/05 14:27:58","message":"a where A=55555"}
diff --git a/event/bench/bench.go b/event/bench/bench.go
index 8329ed8..b5151d7 100644
--- a/event/bench/bench.go
+++ b/event/bench/bench.go
@@ -11,6 +11,7 @@
 	"testing"
 
 	"github.com/google/go-cmp/cmp"
+	"golang.org/x/exp/event/adapter/logfmt"
 )
 
 type Info struct {
@@ -33,7 +34,7 @@
 		"Some other value",
 		"A nice longer value but not too long",
 		"V",
-		"",
+		" ",
 		"ı",
 		"prime count of values",
 	}
@@ -52,7 +53,45 @@
 )
 
 const (
-	TimeFormat = "2006/01/02 15:04:05"
+	TimeFormat = logfmt.TimeFormat
+
+	LogfmtOutput = `
+time="2020/03/05 14:27:48" level=info A=0 msg=a
+time="2020/03/05 14:27:49" level=info B="A value" msg=b
+time="2020/03/05 14:27:50" level=info A=1 msg=a
+time="2020/03/05 14:27:51" level=info B="Some other value" msg=b
+time="2020/03/05 14:27:52" level=info A=22 msg=a
+time="2020/03/05 14:27:53" level=info B="Some other value" msg=b
+time="2020/03/05 14:27:54" level=info A=333 msg=a
+time="2020/03/05 14:27:55" level=info B=" " msg=b
+time="2020/03/05 14:27:56" level=info A=4444 msg=a
+time="2020/03/05 14:27:57" level=info B="prime count of values" msg=b
+time="2020/03/05 14:27:58" level=info A=55555 msg=a
+time="2020/03/05 14:27:59" level=info B=V msg=b
+time="2020/03/05 14:28:00" level=info A=666666 msg=a
+time="2020/03/05 14:28:01" level=info B="A value" msg=b
+time="2020/03/05 14:28:02" level=info A=7777777 msg=a
+time="2020/03/05 14:28:03" level=info B="A value" msg=b
+`
+
+	LogfOutput = `
+time="2020/03/05 14:27:48" level=info msg="a where A=0"
+time="2020/03/05 14:27:49" level=info msg="b where B=\"A value\""
+time="2020/03/05 14:27:50" level=info msg="a where A=1"
+time="2020/03/05 14:27:51" level=info msg="b where B=\"Some other value\""
+time="2020/03/05 14:27:52" level=info msg="a where A=22"
+time="2020/03/05 14:27:53" level=info msg="b where B=\"Some other value\""
+time="2020/03/05 14:27:54" level=info msg="a where A=333"
+time="2020/03/05 14:27:55" level=info msg="b where B=\" \""
+time="2020/03/05 14:27:56" level=info msg="a where A=4444"
+time="2020/03/05 14:27:57" level=info msg="b where B=\"prime count of values\""
+time="2020/03/05 14:27:58" level=info msg="a where A=55555"
+time="2020/03/05 14:27:59" level=info msg="b where B=\"V\""
+time="2020/03/05 14:28:00" level=info msg="a where A=666666"
+time="2020/03/05 14:28:01" level=info msg="b where B=\"A value\""
+time="2020/03/05 14:28:02" level=info msg="a where A=7777777"
+time="2020/03/05 14:28:03" level=info msg="b where B=\"A value\""
+`
 )
 
 type namedBenchmark struct {
diff --git a/event/bench/stdlib_test.go b/event/bench/stdlib_test.go
index 1728208..7b99c74 100644
--- a/event/bench/stdlib_test.go
+++ b/event/bench/stdlib_test.go
@@ -87,9 +87,9 @@
 	now := eventtest.ExporterOptions().Now
 	return context.WithValue(context.Background(), writerKey{},
 		func(msg string, args ...interface{}) {
-			fmt.Fprint(w, now().Format(bench.TimeFormat), " ")
-			fmt.Fprintf(w, msg, args...)
-			fmt.Fprintln(w)
+			fmt.Fprintf(w, "time=%q level=info msg=%q\n",
+				now().Format(bench.TimeFormat),
+				fmt.Sprintf(msg, args...))
 		},
 	)
 }
@@ -111,7 +111,7 @@
 a where A=22
 b where B="Some other value"
 a where A=333
-b where B=""
+b where B=" "
 a where A=4444
 b where B="prime count of values"
 a where A=55555
@@ -124,22 +124,5 @@
 }
 
 func TestLogPrintf(t *testing.T) {
-	bench.TestBenchmark(t, stdlibWriter, stdlibPrintf, `
-2020/03/05 14:27:48 a where A=0
-2020/03/05 14:27:49 b where B="A value"
-2020/03/05 14:27:50 a where A=1
-2020/03/05 14:27:51 b where B="Some other value"
-2020/03/05 14:27:52 a where A=22
-2020/03/05 14:27:53 b where B="Some other value"
-2020/03/05 14:27:54 a where A=333
-2020/03/05 14:27:55 b where B=""
-2020/03/05 14:27:56 a where A=4444
-2020/03/05 14:27:57 b where B="prime count of values"
-2020/03/05 14:27:58 a where A=55555
-2020/03/05 14:27:59 b where B="V"
-2020/03/05 14:28:00 a where A=666666
-2020/03/05 14:28:01 b where B="A value"
-2020/03/05 14:28:02 a where A=7777777
-2020/03/05 14:28:03 b where B="A value"
-`)
+	bench.TestBenchmark(t, stdlibWriter, stdlibPrintf, bench.LogfOutput)
 }
diff --git a/event/bench_test.go b/event/bench_test.go
index 648eeed..5c00395 100644
--- a/event/bench_test.go
+++ b/event/bench_test.go
@@ -14,6 +14,7 @@
 	"golang.org/x/exp/event/adapter/logfmt"
 	"golang.org/x/exp/event/bench"
 	"golang.org/x/exp/event/keys"
+	"golang.org/x/exp/event/severity"
 )
 
 var (
@@ -26,12 +27,12 @@
 
 	eventLog = bench.Hooks{
 		AStart: func(ctx context.Context, a int) context.Context {
-			event.To(ctx).With(aValue.Of(a)).Log(bench.A.Msg)
+			event.To(ctx).With(severity.Info).With(aValue.Of(a)).Log(bench.A.Msg)
 			return ctx
 		},
 		AEnd: func(ctx context.Context) {},
 		BStart: func(ctx context.Context, b string) context.Context {
-			event.To(ctx).With(bValue.Of(b)).Log(bench.B.Msg)
+			event.To(ctx).With(severity.Info).With(bValue.Of(b)).Log(bench.B.Msg)
 			return ctx
 		},
 		BEnd: func(ctx context.Context) {},
@@ -39,12 +40,12 @@
 
 	eventLogf = bench.Hooks{
 		AStart: func(ctx context.Context, a int) context.Context {
-			event.To(ctx).Logf(bench.A.Msgf, a)
+			event.To(ctx).With(severity.Info).Logf(bench.A.Msgf, a)
 			return ctx
 		},
 		AEnd: func(ctx context.Context) {},
 		BStart: func(ctx context.Context, b string) context.Context {
-			event.To(ctx).Logf(bench.B.Msgf, b)
+			event.To(ctx).With(severity.Info).Logf(bench.B.Msgf, b)
 			return ctx
 		},
 		BEnd: func(ctx context.Context) {},
diff --git a/event/event_test.go b/event/event_test.go
index ce4bff9..ca1ffb0 100644
--- a/event/event_test.go
+++ b/event/event_test.go
@@ -38,19 +38,19 @@
 	}{{
 		name:   "simple",
 		events: func(ctx context.Context) { event.To(ctx).Log("a message") },
-		expect: `time=2020-03-05T14:27:48 msg="a message"
+		expect: `time="2020/03/05 14:27:48" msg="a message"
 `}, {
 		name:   "log 1",
 		events: func(ctx context.Context) { event.To(ctx).With(l1).Log("a message") },
-		expect: `time=2020-03-05T14:27:48 l1=1 msg="a message"`,
+		expect: `time="2020/03/05 14:27:48" l1=1 msg="a message"`,
 	}, {
 		name:   "log 2",
 		events: func(ctx context.Context) { event.To(ctx).With(l1).With(l2).Log("a message") },
-		expect: `time=2020-03-05T14:27:48 l1=1 l2=2 msg="a message"`,
+		expect: `time="2020/03/05 14:27:48" l1=1 l2=2 msg="a message"`,
 	}, {
 		name:   "log 3",
 		events: func(ctx context.Context) { event.To(ctx).With(l1).With(l2).With(l3).Log("a message") },
-		expect: `time=2020-03-05T14:27:48 l1=1 l2=2 l3=3 msg="a message"`,
+		expect: `time="2020/03/05 14:27:48" l1=1 l2=2 l3=3 msg="a message"`,
 	}, {
 		name: "span",
 		events: func(ctx context.Context) {
@@ -58,8 +58,8 @@
 			eb.End()
 		},
 		expect: `
-time=2020-03-05T14:27:48 trace=1 name=span
-time=2020-03-05T14:27:49 parent=1 end
+time="2020/03/05 14:27:48" trace=1 name=span
+time="2020/03/05 14:27:49" parent=1 end
 `}, {
 		name: "span nested",
 		events: func(ctx context.Context) {
@@ -70,33 +70,33 @@
 			event.To(child).Log("message")
 		},
 		expect: `
-time=2020-03-05T14:27:48 trace=1 name=parent
-time=2020-03-05T14:27:49 parent=1 trace=2 name=child
-time=2020-03-05T14:27:50 parent=2 msg=message
-time=2020-03-05T14:27:51 parent=2 end
-time=2020-03-05T14:27:52 parent=1 end
+time="2020/03/05 14:27:48" trace=1 name=parent
+time="2020/03/05 14:27:49" parent=1 trace=2 name=child
+time="2020/03/05 14:27:50" parent=2 msg=message
+time="2020/03/05 14:27:51" parent=2 end
+time="2020/03/05 14:27:52" parent=1 end
 `}, {
 		name:   "counter",
 		events: func(ctx context.Context) { event.To(ctx).With(l1).Metric(counter.Record(2)) },
-		expect: `time=2020-03-05T14:27:48 l1=1 metricValue=2 metric=Metric("golang.org/x/exp/event_test/hits")`,
+		expect: `time="2020/03/05 14:27:48" l1=1 metricValue=2 metric=Metric("golang.org/x/exp/event_test/hits")`,
 	}, {
 		name:   "gauge",
 		events: func(ctx context.Context) { event.To(ctx).With(l1).Metric(gauge.Record(98.6)) },
-		expect: `time=2020-03-05T14:27:48 l1=1 metricValue=98.6 metric=Metric("golang.org/x/exp/event_test/temperature")`,
+		expect: `time="2020/03/05 14:27:48" l1=1 metricValue=98.6 metric=Metric("golang.org/x/exp/event_test/temperature")`,
 	}, {
 		name: "duration",
 		events: func(ctx context.Context) {
 			event.To(ctx).With(l1).With(l2).Metric(latency.Record(3 * time.Second))
 		},
-		expect: `time=2020-03-05T14:27:48 l1=1 l2=2 metricValue=3s metric=Metric("golang.org/x/exp/event_test/latency")`,
+		expect: `time="2020/03/05 14:27:48" l1=1 l2=2 metricValue=3s metric=Metric("golang.org/x/exp/event_test/latency")`,
 	}, {
 		name:   "annotate",
 		events: func(ctx context.Context) { event.To(ctx).With(l1).Annotate() },
-		expect: `time=2020-03-05T14:27:48 l1=1`,
+		expect: `time="2020/03/05 14:27:48" l1=1`,
 	}, {
 		name:   "annotate 2",
 		events: func(ctx context.Context) { event.To(ctx).With(l1).With(l2).Annotate() },
-		expect: `time=2020-03-05T14:27:48 l1=1 l2=2`,
+		expect: `time="2020/03/05 14:27:48" l1=1 l2=2`,
 	}, {
 		name: "multiple events",
 		events: func(ctx context.Context) {
@@ -105,8 +105,8 @@
 			b.With(keys.String("myString").Of("some string value")).Log("string event")
 		},
 		expect: `
-time=2020-03-05T14:27:48 myInt=6 msg="my event"
-time=2020-03-05T14:27:49 myString="some string value" msg="string event"
+time="2020/03/05 14:27:48" myInt=6 msg="my event"
+time="2020/03/05 14:27:49" myString="some string value" msg="string event"
 `}} {
 		buf := &strings.Builder{}
 		ctx := event.WithExporter(ctx, event.NewExporter(logfmt.NewHandler(buf), eventtest.ExporterOptions()))
@@ -124,48 +124,14 @@
 	event.To(ctx).With(keys.Int("myInt").Of(6)).Log("my event")
 	event.To(ctx).With(keys.String("myString").Of("some string value")).Log("error event")
 	// Output:
-	// time=2020-03-05T14:27:48 myInt=6 msg="my event"
-	// time=2020-03-05T14:27:49 myString="some string value" msg="error event"
+	// time="2020/03/05 14:27:48" myInt=6 msg="my event"
+	// time="2020/03/05 14:27:49" myString="some string value" msg="error event"
 }
 
 func TestLogEventf(t *testing.T) {
-	bench.TestBenchmark(t, eventPrint, eventLogf, `
-time=2020-03-05T14:27:48 msg="a where A=0"
-time=2020-03-05T14:27:49 msg="b where B=\"A value\""
-time=2020-03-05T14:27:50 msg="a where A=1"
-time=2020-03-05T14:27:51 msg="b where B=\"Some other value\""
-time=2020-03-05T14:27:52 msg="a where A=22"
-time=2020-03-05T14:27:53 msg="b where B=\"Some other value\""
-time=2020-03-05T14:27:54 msg="a where A=333"
-time=2020-03-05T14:27:55 msg="b where B=\"\""
-time=2020-03-05T14:27:56 msg="a where A=4444"
-time=2020-03-05T14:27:57 msg="b where B=\"prime count of values\""
-time=2020-03-05T14:27:58 msg="a where A=55555"
-time=2020-03-05T14:27:59 msg="b where B=\"V\""
-time=2020-03-05T14:28:00 msg="a where A=666666"
-time=2020-03-05T14:28:01 msg="b where B=\"A value\""
-time=2020-03-05T14:28:02 msg="a where A=7777777"
-time=2020-03-05T14:28:03 msg="b where B=\"A value\""
-`)
+	bench.TestBenchmark(t, eventPrint, eventLogf, bench.LogfOutput)
 }
 
 func TestLogEvent(t *testing.T) {
-	bench.TestBenchmark(t, eventPrint, eventLog, `
-time=2020-03-05T14:27:48 A=0 msg=a
-time=2020-03-05T14:27:49 B="A value" msg=b
-time=2020-03-05T14:27:50 A=1 msg=a
-time=2020-03-05T14:27:51 B="Some other value" msg=b
-time=2020-03-05T14:27:52 A=22 msg=a
-time=2020-03-05T14:27:53 B="Some other value" msg=b
-time=2020-03-05T14:27:54 A=333 msg=a
-time=2020-03-05T14:27:55 B="" msg=b
-time=2020-03-05T14:27:56 A=4444 msg=a
-time=2020-03-05T14:27:57 B="prime count of values" msg=b
-time=2020-03-05T14:27:58 A=55555 msg=a
-time=2020-03-05T14:27:59 B=V msg=b
-time=2020-03-05T14:28:00 A=666666 msg=a
-time=2020-03-05T14:28:01 B="A value" msg=b
-time=2020-03-05T14:28:02 A=7777777 msg=a
-time=2020-03-05T14:28:03 B="A value" msg=b
-`)
+	bench.TestBenchmark(t, eventPrint, eventLog, bench.LogfmtOutput)
 }
diff --git a/event/severity/severity_test.go b/event/severity/severity_test.go
index d4e045c..44a94ee 100644
--- a/event/severity/severity_test.go
+++ b/event/severity/severity_test.go
@@ -27,11 +27,11 @@
 	}{{
 		name:   "debug",
 		events: func(ctx context.Context) { event.To(ctx).With(severity.Debug).Log("a message") },
-		expect: `time=2020-03-05T14:27:48 level=debug msg="a message"`,
+		expect: `time="2020/03/05 14:27:48" level=debug msg="a message"`,
 	}, {
 		name:   "info",
 		events: func(ctx context.Context) { event.To(ctx).With(severity.Info).Log("a message") },
-		expect: `time=2020-03-05T14:27:48 level=info msg="a message"`},
+		expect: `time="2020/03/05 14:27:48" level=info msg="a message"`},
 	} {
 		buf := &strings.Builder{}
 		ctx := event.WithExporter(ctx, event.NewExporter(logfmt.NewHandler(buf), eventtest.ExporterOptions()))