you don't want a System 10 anyway, the factory amp provides crap power/sound and it's a pain in the ass to remove to use an aftermarket head-unit amp. Because of it, I can't use my Alpine internal amp which gives much better clarity and punch (power), but have to settle for using my pre-outs alone. The door subs...not that big of a deal, pretty sucky quality. After I bought my latest AT with System 10 I put my Alpine in, hooking it up to the factory amp and the subs crapped out in no time flat. About the only advantage is that it gives you a place to mount some good speakers in the doors and balancing out the front/rear sound. By the time I'm done, the door mounts will be the only part of the System 10 left in my AT. My last AT had the standard 6 speakers and I wish I had that in my new one.