My buddy just bought a 2001 2.5 RS with many sti options on it such as exhaust,wing, and what not. First off, how is the sti exhaust in terms of pipe diameter and weighing against other aftermarket exhausts? Secondly his goals for the car are, keeping it streetable, to get the car deep in the 13's while enhancing the cars appearance. Can you suggest some mods to be done i.e. turbo kits,exhaust, engine eternals, ect... Any advice is appreciated.