The Kenwood eXcelon KMR-XM500 is the better marine stereo overall, rated 2.8 to 2.6. The Kenwood eXcelon KMR-XM500 leads on warranty. The Kenwood KMR-M300BT costs $50 less ($299 vs $349).
Prices were last checked November 9, 2026. Product prices and availability are accurate as of that date and are subject to change; the price and availability shown on Amazon or the retailer's site at the time of purchase apply. As an Amazon Associate we earn from qualifying purchases.
The step-up version of Kenwood’s gauge-hole stereo, for a system that will run external amplifiers. If the stereo will power the speakers directly, the KMR-M300BT does the same job for less.
Amazon $349A full-featured gauge-hole stereo for a small boat or powersports dash. Spend more on the eXcelon KMR-XM500 only if you want its 5 V pre-outs and longer warranty.
Amazon $299Each factor is scored 0-100 against the same fixed reference points for every gauge-hole marine stereo; a clear win is highlighted. How we rank explains each one.
| Factor weight | Kenwood eXcelon KMR-XM500 | Kenwood KMR-M300BT |
|---|---|---|
| Overall rating | 2.8/5 | 2.6/5 |
| Amplifier power 20% | 19 19 W RMS x 4 at 4 ohm | 19 19 W RMS x 4 at 4 ohm |
| Zones 15% | 0 single zone | 0 single zone |
| Pre-amp outputs 10% | 29 3 RCA output sets at 5 V | 29 3 RCA output sets at 2 V |
| Features 25% | 50 SiriusXM-ready, weather band, Bluetooth, USB playback | 50 SiriusXM-ready, weather band, Bluetooth, USB playback |
| Water rating 10% | 70 IP66 front | 70 IP66 front |
| Display 10% | 58 2.7 in color | 58 2.7 in color |
| Warranty 10% | 50 2-year warranty | 0 1-year warranty |
| Kenwood eXcelon KMR-XM500 | Kenwood KMR-M300BT | |
|---|---|---|
| Audio | ||
| Amplifier power (RMS, 4 ohm) | 19 W x 4 RMS | 19 W x 4 RMS |
| Zones | 1 | 1 |
| RCA output sets | 3 at 5 V | 3 at 2 V |
| Sources and control | ||
| Bluetooth | Yes | Yes |
| USB playback | Yes | Yes |
| Phone app | No | No |
| SiriusXM-ready | Yes | Yes |
| NMEA 2000 | No | No |
| Wi-Fi or AirPlay 2 | No | No |
| Weather band | Yes | Yes |
| DAB+ | No | No |
| CD player | No | No |
| Camera input | Yes | Yes |
| Build | ||
| Mount | Gauge hole | Gauge hole |
| Front water rating | IP66 | IP66 |
| Display | 2.7 in color | 2.7 in color |
| Warranty | 2 years | 1 year |
