wats up guys, i just got a g35xs sedan and im looking to buy a carbon fiber diffuser and/or splitter. i would like to know which is the best to get. by best i mean, fitment is good and requires little to no modification to the piece or bumper.

i know this is not interior/exterior related but im also looking to get an exhaust thats not super expensive but also sounds good.

links to pictures, videos, and product pages would be very helpful.