I third the Spintechs!!!! I just switched from Flows 40 series to SPINTECH SPORTSMAN STREETS, both with an off road x from pypes exhaust, and the sound is completely bad-a$$!!! I really like it more than flows, and it is deeper!!
On second thought, don't get them though!!! I don't know of many who have em and i want to stay in the minority!!
I fourth the Spintechs. They sound wicked at 3200 rpms. I have the louder ProStreets (so maybe going with an O/R pipe might be ridiculous - aftermarket catted may be the way to go) and they're stainless steel. I didn't think my car was that loud (because I've gotten used to it and don't really hear it since I drive it) and yesterday a valet pulled out of the lot with my car and I could hear him drive around the block while I was inside the restaurant...and that's with all 4 factory cats...so I can't wait to hear it with 2 high flow cats