I'm looking to install a new perfomance exhaust on my '11 328i Coupe. I realize the performance gains will be minimal so I'm not expecting much. The 2 systems I'm looking at are the Dinan and the Rogue. The Dinan is almost 3 times the price of the Rogue but is a more thorough system that will flow better. The Rogue setup looks great with the polished finish and great welds, but is it a worthy purchase? Which exhaust is the best bang for the buck?