I just installed a Banks cat back system on m 2001 sport. I got it for $225 on ebay, and it sounds really good. Doesnt drone at highway speeds(my BFG A/T's are louder) andits not obnoxiously loud when it idles (the UK has "noise polution"" laws). Did the install myself, and it was really easy, once I got the old exhaust off, but I was having issues with the pipe touching the heat shield on the bottem of the tub and the rear track bar, causing some annoing rattling sounds. Running with no pipe from the muffler till I sort out a solution, so its a bit louder now than it was, but I don't mind the sound.
2001 TJ Sport, 5spd, D44 Rear
33in Duratracs, 3in Currie coils, 1in BL, Bilstien 5100s, MB Razor wheels, Currie Antirock, MetalCloak Duroflex Control Arms