Decent Car B Sound System for Under $600?

I want to know some ideas for getting a Deck, 12" Subwoofer, Amp, and box for up to $600. I like the Pioneer decks, as they seem to work great with my iPod. I've had a Rockford Fosgate sub and a kicker amp suggested by friends, but want to know what other think I can get for up to $600. I dont just want the loudest possible for my money either, i need a balance between loudness and clarity. In other words, a "good" sound.