My buddy, that I work with, wants to put a substage in his Olds Bravada. He is new to car audio. Well sort of his last system consisted of two sony explode 10's and an explode amp and he thought that was loud. He has a budget of $500 and mostly listens to rock. I was thinking maybe 3-4 lower end tens, 2 decent twelves, or one nice 15. I'm sure it won't take much to make him happy but I would like to get him the best his money can buy.