Tracer is referring to my car. I can give you detailed instructions and photos of what to do if you go with the premium system. As for sound... I have a roadster. Road noise, frame squeaks and (on occasion) the top down translates into a pretty lousy listening environment. Audi's 'premium' Bose system is merely okay. I'm a huge music fan, but by no means an audiophile. So it suits my needs. However, if you get the base stock system, you WILL want to replace it.

As for install directly on top of the Bose system... it's a huge pain in the ass, but in the end you'll have a dead stock system with an Empeg. For me it was necessary (I'm leasing) and cheap. SO it's a matter of taste -- if you have extra cash and you will buy the car, I'd say replace the factory system with all new and the Empeg. If you don't have the cash or you are leasing, email me and I'll send you photos and complete instructions on how to get your Empeg in.

Hope this helps!

[edit]
Rereading your post, it's pretty obvious to me that unless you're leasing, you should go with an aftermarket solution. Don't spend an extra dime on Audi/Bose sound, rip out the installation and get what you REALLY want. To be honest, the only thing I regret about leasing my car is my inability to modify it in any real way.
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