If you're upgrading to a 2.5" system, such as the TTI that some people are suggesting, be aware that OEM tips won't fit. TTI offers some very nice replacement tips for both their 2.5" and 3.0" systems.

If you want "relatively" quiet, don't use the Dynomax Ultraflow mufflers. They're a straight-through design and are significantly louder than the standard Dynomax muffler that TTI offers (just can't remember that model's name at the moment).

Also, having a 3" vs. a 2.5" system has nothing to do w/ the engine losing torque. A bigger system simply breathes better and has less restriction... and is a bit louder.

FWIW, I have TTI 2" headers, their 3.0" X-pipe system w/ Dynomax Ultraflows, and their replacement tips. Cheap? NO. But their stuff is high quality and usually fits w/o TOO much hassle (but not necessarily NONE).