I found this muffler on amazon and it has some good reviews I'm considering it for my car
Amazon.com: DC Sport EX-5015 Stainless Steel Round Muffler and Slant Cut Exhaust Tip: Automotive
It's supposed to sound pretty good but my idea is that since it's smaller than my stock muffler it could make a belly pan easier and I could possibly get rid of some of the heat shielding. I'm going to look for a video on it just to actually hear it but since it's so cheap I don't have much to lose but the reduced weight and backpressure will mean a small hp gain and fuel economy improvement as well and since it's only ~$40 it should pay off pretty quickly. Finally it will be one more step in my battle against rust too lol.