Can someone tell me if the sound quality for music via the aux-in is comparable with for example the Bose quiet comfort 3 bose headset?
Cant answer your question specifically but can tell you that the music quality on the A20 is way better than acceptable. I use this with the iPhone streaming audio via a Bluetooh connection, and with an XM entertainment radio and the results are IMHO quite good taking into consideration that one is flying along in a noisy contraption known as a helicopter. Of course not up to high end studio headphones such as the Sennheiser HD800 but then you really cant use these in a helicopter.