[shakko]

Just wanted to mention that I went ahead and purchased the Griffin BlueTrip AUX (without having read this thread) and definitely noticed a lack of bass in my music. The difference between plugging in the supplied aux cable directly from iPhone to the aux in port versus using the bluetooth is night and day. The bluetooth sound is far less bassy, but the highs came over just fine.

I was really hoping to get a wire-free solution and still maintain a decent level of audio fidelity, but no bass (like GChase mentioned) kills this little accessory.