While many say the RNS-E sounds better than the Symphony II head unit, it uses the same GALA/DSP/BOSE features. If your car has Bose now, you will have the same after upgrading to the RNS-E. One option of course is to remove all Bose/Audi components, install a quality multi-channel amp and new speakers and code the head unit for a non-Bose system. You can use the line out to drive your 3rd party amp - with either the RNS-E or the Symphony head unit. Together with a 3rd party EQ you may get better sound but with any non-OEM head unit you will loose the center display.