Did you try the coffmans with stock ecu? Mines stock and love the look of the Coffman, not really on a budget so I'm not buying it cause it's cheap I just like the minimalistic look of it, I also considered the Vance and Hines but it's a big muffler like most slip ons. I'm so confused on what to buy!!!!!
If want something that sounds the nuts get a danmoto xg1. Then buy a powercommander. Im going to take mine to the dyno soom so ill have an optimized map. Ive been playing with it a bit and its great