would'nt a sti axleback create a bottle neck considering he's going from3" piping to 2.5?
This depends on if you wanna keep the rumble or not, hands down I believe a SPT muffler is the quitest aftermarket one out there, and it keeps the rumble. STI muffler you won't hear the rumble unless ur standing right next to it outside. I had the same problem and just bought a SPT muffler off a 10 wrx sedan and just cut/welded to my own piping. Sounds great.