I currently own an xtant 603x and love it (even though i'm selling it

), it sounds nicer then my previous pheonix gold zx475 amp.
i would strongly advise to dynamat the doors in addition to cowboy's insulation kit.
the sub is the same one i have as well and it's awesome for the price. wont get you w7 performance but you are spending a fraction of what the w7 goes for.
check out "ticketbait's" install too:
http://forums.corvetteforum.com/show...12&forum_id=20
he has the clean sweep in his c6 and loves it.