From what I hear, most O/R X pipes are the same. But personally, I like Bassani and Magnaflow products. I feel (in my opinion) that you can never go wrong with them but I'll say again, I dont think there's too big of a difference in O/R X pipes
2008 Mustang GT/CS: 5 speed | FRPP 4.10 Gears | Bama 93H Tune | Magnaflow Magnapacks | Bassani O/R X Pipe | Airaid CAI | MGW | J&M LCAs (to be installed)
Upcoming: GT500 Supercharger (Department of Boost), 19" Koko Kuture Sardinia-5 Wheels, etc.