Sparks Fails

Well I changed my muffler about 2 months back and the paint has already worn off and is starting to rust. I have more money available to me than I did last time, so I'm looking to get something quality. Maybe even dual exhaust I'm not sure. What are your guys recommendations when it comes to getting a new muffler fitted for dual exhaust? I have a 3.8L V6 but even with the shitty muffler I have on now has a very nice deep sound. Looking for the same sound just much louder. I currently have the "Flowtech Terminator". Thanks.