Best exhaust combo I have heard is Red Devil's. I believe it is a Tannabe exhaust. I know he has the RP Supercat.

I've also gotten a lot of compliments on the sound of my setup.

 

I have the Agency Power exhaust. I like it, but dont love it. Anyways I ordered up the Mazsport Ignition Solution about a week ago. I will post back to see if my butt dyno feels anything after the instal. I mainly bought it because I've heard such bad things about the coils in our cars. Plus I'm due for a plug change and figured might as well do the whole shabang.