Picked up my new-to-me 335d last week and it took a few seconds to accept that the base audio system in 2010 was beyond bad; truly it is an insult to the ears. I quickly began pouring over the forums looking for upgrade ideas and I settled on Musicar NW.
I have a 2012 MINI Cooper JCW with the Integral Audio Soundstage installation
and it is a fantasticly designed and implemented system that requires very little non-reversible modifications. I wanted something similar for the new car and I think I have found it.
So now I am here, waiting (im)patiently for my goodies to arrive, bookmarking every good piece of information I can find. I will be filling out this post as I get into the installation.