Both Stingers and the Bullets are great systems but loud like Manny said. Once you add headers, I found them to be unbearable. It was impossible to carry a conversation in the cabin over the drone of the exhaust.
I found that the perfect combination for me with headers was the Z06 titanium system with a 1.5" bypass. It should be fairly easy to find the exhaust, but could be tricky finding someone who can weld the titanium. The sound was almost exotic. It wasn't a deep sound at all, but very pleasing to my ears. At cruise you can hear the exhaust, but it was a nice "you know it's there" sound but it never got in the way. Once you got on the throttle, it came alive.
Come out to our summer get togethers and hear the cars for yourself. If you're interested in hearing what my C5 sounded like, I can probably set something up with the gentleman who bought the car from me for you if you'd like.