I have an '01 Jeep Cherokee sport, and it has the original cassette sound system from when it was new. I want to upgrade it to a good system. I don't need crazy amounts of bass, but some bass doesn't hurt. I am picky on my sound. Are there any recommendations on speakers and a reciever to get? Should I get 1 or 2 subs? For a receiver, I would prefer one with cd/ipod compatibility. Bluetooth and one of those retractable screens would be nice, too. Also, what kind of speakers do the doors take? (I hope I'm not limited to oval speakers...) I am willing to spend about $700, and I am looking for at least decent quality equipment. Thanks for your help in advance.