Well I went and threw on a Magnaflow catback and all I have to say is WOW! I love this sound, its sooooooo freak'in smooth! I liked the 2ch flows but they were too raspy and the resonance killed me on the freeway. I also noticed a significant power increase up top. About crapped my pants hopping on I-5 Would recommend Magnaflow to anyone, the only drawback is the price, but it comes with a lifetime warrenty if you have it professional installed. BTW those mufflers are the brightest part of my car right now