If you are referring to an axle-back or cat-back as people call them, the point is for sound and looks. But a tune will wake the car up. Intake work is more important on these cars. You have an LS6 intake manifold, so that is nice, now do a high flow filter, or look up the flip tie mod, and possibly port the throttle etc. These will give better response and some power gains. If you do an exhaust, do an x-pipe with it to make it worth while.
Brand is just a matter of preference. Everyone will come on here and tell you what they have and why its the best. They are all the same though. If you want sound, look for the small or lack of mufflers. If you want quiet, any systems with full size mufflers will stay quiet.
Last edited by NukeC5; 10-06-2012 at 04:07 PM.