ok basically on an 00GT you're looking at 3 major sections of the exhaust..headers, midpipe (xpipe), and catback. Is this correct? I don't want longtubes for certain reasons and from what I hear shorttubes really aren't even worth the time and effort. If I go with a catback alone and maybe down the road upgrade the TB and plenum, is that going to make a pretty decent gain for me as far as a little more kick and better throttle response? How much more of a difference would an aftermarket x-pipe make in addition to these? I'm looking at the Bassani BX catback priced at around $489.