Just picked up an 03 A4 1.8T last week and am starting to read about the endless mods people do to these cars. I have a sub/amp from my last car I'd like to hook up but have read a few posts about the bose system not really like add ons. Any suggestions or comments? I have a really nice set of infinity components and a second amp but I'm figuring that is probably out unless I replace the whole bose system.