We compare products from their published specs and features; the verdicts below are our independent editorial opinions.
Updated: 2026-09-17 · 6 min read · Independent comparison
If you want a purpose-built workout earbud with the longest battery story and a rugged, no-nonsense black look, choose Keenso 5.4; if you need a charging case that doubles as a flashlight and a head-turning skull design, choose VIVIDUS M20.
• Keenso 5.4 — biggest strength: A serious battery system. 7 hours on a single charge and up to 42 hours total with the charging case, plus an LED display on the case so you can see what's left instead of guessing.
• Keenso 5.4 — biggest trade-off: It plays it safe on design. Plain black, in-ear, built for function. Nothing about it is meant to turn heads, and the feature list is narrow by design.
• VIVIDUS M20 — biggest strength: The case does double duty. It's a large charging box with an LED battery percentage readout and a built-in flashlight, so it earns its place in a bag or glovebox.
• VIVIDUS M20 — biggest trade-off: The battery story is thinner on paper. You get a 1.5-hour charge time and multiple recharges from the case, but no single-charge or total-playtime figure is published, so the Keenso is the safer bet if runtime is your priority.
• Pick Keenso 5.4 if you're a runner, gym-goer or meeting-hopper who wants long playback, a light case and touch controls without fuss.
• Pick VIVIDUS M20 if you want personality plus a practical extra — skull styling, a mirror finish, and a flashlight case you'll actually reach for.
The Keenso 5.4 is the earbud equivalent of a well-worn pair of running shoes. It doesn't try to impress you on looks. It tries to disappear into your routine. The spec sheet reads like a checklist written by someone who actually works out: 7 hours on a single charge, 42 hours total with the case, a 10-meter wireless range, and touch controls for playback, volume and calls. That last part matters more than people admit. Mid-run, you don't want to dig a phone out of an armband. You tap the earbud. Done. The LED display on the charging case is the quiet hero here — it shows remaining battery and charging status, so you know before you leave the house whether you've got a full session in you or a half one.
Who should buy it: Runners, cyclists, lifters, and anyone who treats earbuds as gear rather than a fashion item. If you've ever had earbuds die at mile four, the 42-hour total figure is the entire pitch. Who should skip it: If you want earbuds that make a statement, or you specifically want a case that does something extra beyond charging, this isn't that product. It's competent and focused, not flashy.
VIVIDUS M20: Who It's For
The VIVIDUS M20 goes the other direction entirely. Where the Keenso hides, the M20 announces itself. Skull-themed earbuds with a mirror surface finish, sitting in a large black ABS case that measures about 3.5 by 2.5 by 1.5 inches and weighs 2.5 ounces. That's a chunky case — noticeably bigger than a pocketable pill-shaped one — but it's big for a reason.
That reason is the feature that separates the M20 from almost everything in its lane: a built-in LED flashlight in the charging case. Think about where that lands. A glovebox. A nightstand. A hiking pack. A power outage. It's the kind of extra you don't think about until the one time you need it, and then it's the only thing you care about. Add the LED display showing battery percentage at a glance, and the case becomes a small utility object that happens to also charge your earbuds.
On the audio side, the M20 lists a 13.4 mm dynamic driver, 32 ohm impedance, 20 Hz frequency response, 98 dB sensitivity and 40 ms latency. That driver size is worth noting — it's a large dynamic driver, the sort of spec that usually corresponds to fuller low-end output. The low 40 ms latency figure is aimed squarely at gamers and video watchers, where audio lag is the thing that ruins the experience. Bluetooth 5.3 with a 33-foot range covers normal apartment and gym distances comfortably, and the case charges in about 1.5 hours. You also get touch controls, passive noise cancellation, and a waterproof rating — plus fast charging and a lightweight build. Warranty is one month, which is short, so factor that in.
Who should buy it: Gamers, commuters, students, and anyone who values a distinctive look and a case that pulls double duty. Who should skip it: If long, documented battery life is your number one criterion, the Keenso gives you hard numbers the M20 doesn't.
Side-by-Side: Which Should You Choose?
• Best for long, quantified battery life → Keenso 5.4. 7 hours per charge, 42 hours with the case, spelled out clearly.
• Best for a case that does more than charge → VIVIDUS M20. LED percentage readout plus a built-in flashlight.
• Best for running and gym sessions → Keenso 5.4. 10 m range, ergonomic in-ear fit, touch controls built for movement.
• Best for standing out → VIVIDUS M20. Skull design with a mirror surface finish, in black.
• Best for travel and everyday carry utility → VIVIDUS M20. The flashlight case earns its bulk in a bag or glovebox.
• Best for the longest warranty coverage → Keenso 5.4. 90 days versus the M20's one month.
• Best for a simple, no-distraction setup → Keenso 5.4. Fewer moving parts, fewer things to think about.
In my opinion, the Keenso 5.4 is the smarter buy for most people. The reason is boring but decisive: battery life you can plan around. Seven hours per charge and 42 hours total, with a case display that tells you exactly where you stand, is the single most useful thing an earbud can offer someone who actually uses them. The M20 is genuinely more fun and the flashlight case is a legitimately clever idea — but the shorter warranty and the absence of published playtime figures make it the riskier pick if runtime matters to you. If you want personality and utility, go VIVIDUS. If you want to stop thinking about charging, go Keenso.
The Keenso 5.4 is the better fit for running. It's built around an ergonomic in-ear design, a 10-meter range and touch controls for playback, volume and calls — all things you want when your hands are busy and your phone is strapped to your arm.
Yes. The M20's large charging case includes an integrated LED flashlight, which is the feature that most sets it apart from the Keenso. It also has an LED display showing remaining battery percentage.
The Keenso 5.4 publishes the clearer numbers: 7 hours on a single charge and up to 42 hours with the charging case. The VIVIDUS M20 lists a 1.5-hour charge time and multiple recharges from its large case, but no single-charge or total playtime figure.
I don't quote prices here because they change often — use the button on this page to check the current price on Amazon for each. On features alone, the Keenso 5.4 wins on battery and warranty length, while the VIVIDUS M20 wins on design, driver size and the flashlight case.
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