I run Kooks 1 7/8 headers and high flow cats, straight all the way back with Magnaflow mufflers. No X-pipe or H. You can hear the lope in my stock cam. I had the guy run 2 1/2" piping after the cats just so I had some back pressure. The car is also Procharged. It's a daily driver and I don't want to burn up heads. Remember back pressure is good at the same time you want as little as possible. The car sounds good and in the cab it gets noisy when i stomp on it.
You don't really need back pressure.
2003 Corvette Z06 - MGW shifter, Corsa X pipe, Corsa Xtreme exhaust, Texas Speed long tubes w/o cats, PowerStop rotors/pads, Conti DWS tires, C6Z51 F&R sways, C5R headlights, tuned
04 GTO - sold