Does anyone know a lot about exhausts? I was contemplating the pettit or Bonez down pipe but I have idea what is better. I'm gonna buy a new 7 next year but I want to get some details first.
I'm ready for something newer

 

off to appropriate forum...

 

I am assuming you mean the APEXi GT Spec exhaust, I have never heard of one from Greddy. This is only a cat-back system, and from what I've heard its is one of the most free-flowing ones you can buy, but they are loud as ****. There can't be much difference between the downpipes, just get the biggest one possible, rotaries need it.