Two Coupes with some similarities, but otherwise different in most aspects such as the modifications, starting price, horsepower, fuel economy, ground shadow size, and height. First of all, there is a $55,000 difference in the base MSRP. The 2015 Mercedes-Benz S-Class Coupe S 65 AMG has a higher starting price than the 2016 Porsche 911 Coupe GT3 RS. Also, the 2015 S-Class Coupe S 65 AMG has a more powerful engine than the 2016 911 Coupe GT3 RS, and it gets 2 fewer miles on a gallon of fuel. In addition, the S-Class Coupe S 65 AMG body is slightly larger than the 911 Coupe GT3 RS, and in addition to that, it's also taller. Among similarities are the body structure, market segment, and maximum occupancy.