I would get a PC. Right fuel map will make a big difference. Don't think you can download a fuel map for that exhaust. Last time I was at the dynojet website there was a 2 bros. and a akra map available. Hesitation is probably caused from running too lean when you get on it or certain rpms. I have the akra exhaust with a PC. I can't say I feel hesitation but sometimes it feels like it doesn't wind up quick enough in the low to mid rpm range. Once I get above it, smoother than stock exhaust. Maybe lowering front sprocket to a 16T would make a difference.