I have ACC on my stock 17s and the difference is marked. Just drive over a speed hump and you'll feel a huge difference between comfort and sport.
ACC was a must for me when ordering.
The Sport mode also makes the steering a little more responsive and handles corners like a rock.
IMO - an excellent $1500 option.
2011 Audi A5 Sportback 2.0TFSI S-Tronic Quattro | Deep Sea Blue | 18" Audi exclusive 10 spoke | Bang & Olufsen | MMI Plus Nav | Advanced Parking & Reverse Cam | Sunroof | Sports Suspension | Xenons | Walnut Inlays || Previously: MkVI GTI | Carbon Steel Grey | DSG | ACC | Dynaudio | Reverse Cam | "R" LED Tail Lights | APR Stage 1
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