Audi needs to turn in a winning performance on the sport/luxury stage if it wants to compete head-to-head with BMW and Mercedes-Benz. The S5 is Audi's move to capture buyers who might otherwise select a BMW 335i or Mercedes-Benz CLK 350 Sport. With V8 power coupled with quattro all-wheel-drive – two features the competition lacks – we'd say Audi's got a good shot at conquest sales from BMW and Benz intenders.