Interior and back-seat space is also a bit better than in other rear-wheel-drive European sport sedans, and the interior appointments themselves stand out as more fashion-forward. Audi claims best-in-class fuel economy for the 2.0T model, which achieves up to 24 mpg city, 33 highway. Meanwhile, the S6 remains a performance standout--this time with improved mileage, yet with stronger performance than ever