Maybe the speakers sound cheap, but it's not like you can make open-mounted 3.5" speakers in the dash sound good either. I'd be curious if anybody has found a better speaker that fits in there or a way to go 5.25". Limiting it to 4" was probably done for depth reasons, but it also kind of kills the concept. I would think you could dyna-mat the sheet metal and then put that highliner in. Probably $450 to your door, which seems kind of high for what it is (plus sound deadener, plus paint), but I don't think there's any competition.