I just got and Interphone F4 for my helmet and it's awesome! Has low profile speakers and is Bluetooth. I don't crank the volume, just enough to hear it and I know the songs, it also has a feature that when you start going faster it gets louder and vise versa which makes it nice to have it at a good volume while in the city but when I jump on the highway it ramps up the volume. My $0.02