The difference is incredible. The subwoofer really comes alive now. The maximum output rating on the ADB340MP is 50x4 with a continuous output of 17x4. Take those with a grain of salt, but I believe they're a bit higher that stock. It's running through the RF amp. The Clarion unit seems to have a bit more adjustability that the RF unit (hi/mid/low adjustments + builtin EQ with a few presets), and also has some low end enhancement that you can enable. But it sounds great and now I can hook my iPod in through an actual AUX-in instead of using a modulator. Also, the ADB340MP has CD and cassette. And it doesn't look out of place either, unlike some aftermarket HUs. I prefer a more conservative look, but those can be hard to find.