Thanks for the info guys. Ever since I took delivery I have been slightly disappointed with the sound from my exhaust and it never sounded quite like some other 7's I've heard. I even had passengers comment on how civilized they found my car! I solved this by removing the cat and fitting the R500 box which made a huge difference. I'm hoping the RBTB will add even more character to the exhaust note. I don't want to blast everyone away, I just want the car to sound how it looks, if you know what I mean. Out of interest the CC upgrade is from 175 to 220 but my car as standard is 180bhp. Will the upgrade make it up to 225?? Buds