This would probably be my second, maybe third, favorite mod on the car (1st being the 3" Invidia turbo back exhaust, possible second is the GrimmSpeed stage 1 kit). It is one of the most precise and well built looking pieces of gear for my WRX. They clearly take no chances with their reputation. I had this installed along with the turbo back exhaust and then an immediate pro-tune . The thing sounds amazing. Definitely recommend.