x2 and I'd definitely go the used route, caco is great and so is the f/s section here.
Audioque is way cheaper than a sundown but I heard if your electric isn't the greatest than it suffers, but if your going to upgrade your alt and get some xs batteries it should be fine, not to mention you can run the a.q's at 16 volts, idk if you can do that with the sundowns.