Two Sedans with more similarities, such as the body structure, market segment, starting price, and height, than differences, like the modifications, horsepower, fuel economy, ground shadow size, and maximum occupancy. First of all, the 2016 Mercedes-Benz CLS-Class AMG CLS 63 S 4MATIC has a more powerful engine and gets 2 mpg less than the 2015 Audi S8. Also, the 2015 S8 is slightly larger than the 2016 CLS-Class AMG CLS 63 S 4MATIC. In addition, the S8 seats one more passenger than the CLS-Class AMG CLS 63 S 4MATIC. Among similarities are the body structure, market segment, starting price, and height.