They are stupid. The light will go off if you change the intake pipe as the car has a sensor in it. It does not damage the car but will have the check engine light come up. PPE header and mid pipe, HKS silent hi-power catback, 440cc injectors, DD intake manifold, 2.5 CAI(Blitz pod) ,MWR 190lph fuel pump and PFC and a tune. That will get you 130kw at the wheels. The standard exhaust manifold is decent as it is and if you get it ported it will save a lot of money and do a very similar thing. The exhaust is a matter of sound really. The muffler is set up before the rear sub frame and so the tail pipe comes out from it at a funny angle. It is a matter of how it looks mostly. Megan racing make a okay one that is shiney. Sorry about the bold lettering, could not change it lol