My brother wanted me to ask about his car looking for some bolt-ons. he has a 2011 outback sport hatch Will the exhaust for the wrx/sti fit? will it cause problems being a 3" system? or would it just be better to cut off stock muffler and replace with a performace muffler" He is already aware that there is not alot of power to be made just wants it to sound better and if it adds some power great. Any other parts you can think of that will fit to help performance would be appreciated