I have a C4S with X51,-20mm and LSD. The sound is great, the 997 tt sound is horrible compared to the X51. The driving feeling of -20mm/LSD is superior to 997 tt PASM, but you can choose LSD on 997 tt. The speed and the power of the turbo is great you can't compare it to your X51. I have decided and will change my car in 2 month. I wil get a 997 tt with manual. The turbo isn't to fast. It is a very secure way of driving 480 hp.

Go on and trade for 997 tt.

AM