We installed ARH LT headers with HF catted pipe and stock mufflers on an L99 and then custom tuned with HP Tuners. Sounded great, just on the edge of being a little loud at WOT. Can't imagine how loud it would be with aftermarket catback.
10 Camaro Magnacharged- 595rwhp/585rwtq, full exhaust, Pedders Justice/ZL1 sway, Stoptech brakes and 21" 3 Pc. Forgeline wheels
99 Corvette- 497rwhp/490rwtq-402 N/A, 6pis/4pis brakes...fun track car/daily driver
2010 Camaro 2LT/RS...257rwhp/234rwtq SLP CAI and IAT relocated, Eibach springs and Flowmasters