Pierre,
I have an S3 with a rear Librands Sports Exhaust (quad pipes). I've only had my Aero 6 weeks and spent some considerable time searching for a car with this as part of the configuration. The sound is fantastic (old school grunt) and I love the way the car looks from the rear - proper mean !! With the side exhausts I didn't like the the look of the car from the rear.....a gap where something was missing.
Each to their own......but I'd personally choose rear Librands over side exhausts every time.
You definetly need the diffuser then it looks great.
For me Side exhausts because its so different to any other car , then fit SS exhaust's and finally an agreeable credit card
