diff --git a/cmd/spinifex/cmd/admin.go b/cmd/spinifex/cmd/admin.go
index d4e2f5cbb..10b0dff31 100644
--- a/cmd/spinifex/cmd/admin.go
+++ b/cmd/spinifex/cmd/admin.go
@@ -707,7 +707,25 @@ func runimagesImportCmd(cmd *cobra.Command, args []string) {
 	// command, which would collapse the path to a relative config/ca.pem.
 	bakeCACertIntoImage(extractedImagePath, filepath.Join(baseDir, "config", "ca.pem"))
 
-	err = v_utils.ImportDiskImage(&s3Config, &vbConfig, extractedImagePath)
+	// Render the flush bar here rather than inside viperblock, which stays a
+	// pure storage library. The bar is built lazily on the first update so it is
+	// never drawn if the import fails before any bytes flush; viperblock
+	// throttles the callback to ≤101 invocations, so the human-readable title
+	// renders without the per-block render-frequency regression.
+	var flushBar *pterm.ProgressbarPrinter
+	var flushUpdate func(current uint64)
+	progress := func(current, total uint64) {
+		if flushBar == nil {
+			flushBar, flushUpdate = utils.NewByteProgressBar("Flushing image to storage", total)
+		}
+		flushUpdate(current)
+	}
+
+	err = v_utils.ImportDiskImage(&s3Config, &vbConfig, extractedImagePath, progress)
+
+	if flushBar != nil {
+		_, _ = flushBar.Stop()
+	}
 
 	if err != nil {
 		fmt.Fprintf(os.Stderr, "Could not import image to predastore: %v\n", err)
diff --git a/go.mod b/go.mod
index 3fa6e7664..7af8cba6c 100644
--- a/go.mod
+++ b/go.mod
@@ -22,7 +22,7 @@ require (
 	github.com/miekg/dns v1.1.72
 	github.com/mulgadc/northstar v1.13.0
 	github.com/mulgadc/predastore v1.13.1-0.20260722023246-c0a90d23b3a0
-	github.com/mulgadc/viperblock v1.13.1-0.20260723031009-8a2df5653734
+	github.com/mulgadc/viperblock v1.13.1-0.20260723043425-b78e24c374d5
 	github.com/nats-io/nats-server/v2 v2.14.3
 	github.com/nats-io/nats.go v1.52.0
 	github.com/opencontainers/runtime-spec v1.3.0
diff --git a/go.sum b/go.sum
index 7f0888a55..704010017 100644
--- a/go.sum
+++ b/go.sum
@@ -1321,8 +1321,8 @@ github.com/mulgadc/northstar v1.13.0 h1:L9PyYZ9Klg7dv2kE5+DHOcgPHelaZRDIvnwBsbHs
 github.com/mulgadc/northstar v1.13.0/go.mod h1:erQE/PzK9UMtgH8Y+uI5RdiboO/nqe1CUJbIpkae/FM=
 github.com/mulgadc/predastore v1.13.1-0.20260722023246-c0a90d23b3a0 h1:29g+uPZ0LAANVA1IPnE/ogxJzJBJnBZvnTl51icp378=
 github.com/mulgadc/predastore v1.13.1-0.20260722023246-c0a90d23b3a0/go.mod h1:38YSuk9zvYmbmgyM13WTkIQPJtvo2KmGJBYJul6NeAE=
-github.com/mulgadc/viperblock v1.13.1-0.20260723031009-8a2df5653734 h1:BFR0RwNMxCwUONqaBvK1eo8wlLPcnAsaHnDon4jhg8A=
-github.com/mulgadc/viperblock v1.13.1-0.20260723031009-8a2df5653734/go.mod h1:HMIDtq9NhuRYxmeAyZiqbYwoIpHF4wmMujk9PLW7Tzg=
+github.com/mulgadc/viperblock v1.13.1-0.20260723043425-b78e24c374d5 h1:owinBKFK8AHM5XPtrVR27zhzakkqVOciLUjtvmxMvx4=
+github.com/mulgadc/viperblock v1.13.1-0.20260723043425-b78e24c374d5/go.mod h1:ilr5G8RIkY441fZuRZeO4zPj9cZBsdUUPYjuXJ+cDRg=
 github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 h1:C3w9PqII01/Oq1c1nUAm88MOHcQC9l5mIlSMApZMrHA=
 github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822/go.mod h1:+n7T8mK8HuQTcFwEeznm/DIxMOiR9yIdICNftLE1DvQ=
 github.com/mwitkow/go-conntrack v0.0.0-20161129095857-cc309e4a2223/go.mod h1:qRWi+5nqEBWmkhHvq77mSJWrCKwh8bxhgT7d/eI7P4U=
diff --git a/spinifex/utils/conversion.go b/spinifex/utils/conversion.go
index d488b7198..ecc5d446c 100644
--- a/spinifex/utils/conversion.go
+++ b/spinifex/utils/conversion.go
@@ -36,3 +36,11 @@ func SafeUint64ToInt64(v uint64) int64 {
 	}
 	return int64(v)
 }
+
+// SafeUint64ToInt converts uint64 to int, capping at math.MaxInt.
+func SafeUint64ToInt(v uint64) int {
+	if v > math.MaxInt {
+		return math.MaxInt
+	}
+	return int(v)
+}
diff --git a/spinifex/utils/utils.go b/spinifex/utils/utils.go
index 1e567e4ea..26b4bc402 100644
--- a/spinifex/utils/utils.go
+++ b/spinifex/utils/utils.go
@@ -203,13 +203,21 @@ func DownloadFileWithProgress(url string, name string, filename string, timeout
 	cl := resp.ContentLength
 
 	if cl > 0 {
-		bar, _ := pterm.DefaultProgressbar.
-			WithTitle(fmt.Sprintf("Downloading %s", name)).
-			WithTotal(int(cl)).
-			Start()
+		total := SafeInt64ToUint64(cl)
+		bar, update := NewByteProgressBar(fmt.Sprintf("Downloading %s", name), total)
 
+		// io.Copy writes ~32 KiB per TeeReader call, so gate rendering on
+		// integer-percentage change to cap the bar at ≤101 renders instead of
+		// re-rendering tens of thousands of times.
+		var current uint64
+		lastPct := -1
 		reader := io.TeeReader(resp.Body, progressWriter(func(n int) {
-			bar.Add(n)
+			current += SafeIntToUint64(n)
+			pct := SafeUint64ToInt(current * 100 / total)
+			if pct > lastPct {
+				lastPct = pct
+				update(current)
+			}
 		}))
 
 		_, err = io.Copy(f, reader)
@@ -246,6 +254,35 @@ func (pw progressWriter) Write(p []byte) (int, error) {
 	return len(p), nil
 }
 
+// NewByteProgressBar starts a pterm progress bar that renders human-readable
+// sizes in its title instead of raw byte counts, and returns an update func
+// that performs one render per call. Callers must invoke update at a throttled
+// cadence (integer-percentage change) — the render itself is expensive, so an
+// unthrottled per-write call regresses throughput.
+//
+// pterm's elapsed-time display normally spawns a background goroutine that
+// re-renders every second with no lock, tearing the line against our own
+// low-frequency renders. Starting with it off means no timer is spawned; the
+// flag is then set on the returned bar so pterm still appends its "| 9s"
+// suffix, now emitted only on our (single) renders.
+func NewByteProgressBar(title string, total uint64) (*pterm.ProgressbarPrinter, func(current uint64)) {
+	totalHuman := HumanBytes(total)
+	bar, _ := pterm.DefaultProgressbar.
+		WithTitle(title).
+		WithTotal(SafeUint64ToInt(total)).
+		WithShowCount(false).       // hide raw ints; the size goes in the title
+		WithShowElapsedTime(false). // suppress the async re-render (see above)
+		Start()
+	bar.ShowElapsedTime = true // keep pterm's elapsed, rendered only by us
+
+	update := func(current uint64) {
+		bar.Current = SafeUint64ToInt(current) // drives fill + percentage
+		// UpdateTitle performs the single render for this step.
+		bar.UpdateTitle(fmt.Sprintf("%s — %s / %s", title, HumanBytes(current), totalHuman))
+	}
+	return bar, update
+}
+
 // HumanBytes formats a byte count using IEC binary suffixes (KiB, MiB, ...).
 // Values below 1024 render as exact bytes.
 func HumanBytes(b uint64) string {