Replacing your head unit does nothing when it comes to wattage being pushed to the speakers. Your BMW head unit feeds a low power signal to it amp in the trunk, and that AMP is what pushes out the power to the speakers. If your head unit is pushing more power than it should to the amp then you will get a bad signal. If you bypass the amp, then your speakers will sound quiet and under powered. If you wanted a drop in model than you should have just waited another month and collected to by a real Dynavin from Jeff. I own the D95 android unit, Dynavin is a good unit, but not with out a few bugs, getting a knock off verison to save $100 is not worth it.
There is very little support for the knockoffs, and you will get very little help, but if you have the Dyanvin than E46 fanatics will be able to help you fix any issue you have