The S6 is a high performance version of the A6 introduced by Audi in 1994.

• "This high-performance variant of the A6 is Audi's answer to BMW's V-10-powered M5. However, the S6 is intended as a fast touring car rather than an out-and-out road racer."—Car and DriverCar and Driver: Audi S6 Capsule Review

• "The 2008 Audi S6 is a well-crafted sports sedan, but when compared to its two key competitors, it falls behind in terms of maximum performance and driver enjoyment."—Edmunds.comEdmunds: 2008 Audi S6 Review

• "Overall, the S6 is a nearly perfect long-distance machine. In my mind, it could only be improved with the addition of a stick shift. It’s comfortable and relaxing to drive, but with monstrous power on tap it can provide plenty of excitement as the miles pile up."—Forbes AutosForbes Autos: Audi S6 Test Drive

• BMW M5
• Mercedes-Benz E65 AMG
• Cadillac STS-V