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 

I'll just show up at BM once this weather clears up