Two Sedans with some similarities, but otherwise different in most aspects such as the modifications, starting price, horsepower, fuel economy, and ground shadow size. First of all, the 2017 Mercedes-Benz S-Class Sedan AMG S 65 is priced $77,770 lower compared to the base MSRP of the 2017 Bentley Mulsanne. Also, a bigger engine usually means less mpg. But the 2017 S-Class Sedan AMG S 65 has a more powerful engine and it gets 2.5 more mpg than the 2017 Mulsanne. In addition, the Mulsanne has a slightly larger body than the S-Class Sedan AMG S 65. Among similarities are the body structure, market segment, height, and maximum occupancy.