For your head unit either Alpine or Pioneer. When it comes to the subs I would suggest Pioneer (Premier of course) or JL Audio. When it comes to the factory system, I only heard a few that have aftermarket speakers, mostly consisting of pioneer and the sound was very clear and crisp. I guess when I look at it, I would go with pioneer, but not the pioneer equipment sold in Circuit City or Best Buy. One more I would suggest which is actually pretty cheap and is starting to get alot of rep, especially where I am from is the Fusion series. I was very surprised in the sound. But then again, you can only get these through a dealer.
