Two Coupes with some similarities, but otherwise different in most aspects such as the model year, horsepower, fuel economy, and maximum occupancy. First of all, a bigger engine usually means less mpg. But the 2013 E-Class Coupe has a more powerful engine and it gets 1.5 more mpg than the 2016 S5 Coupe. Also, you'll seat two more passengers in the E-Class Coupe than in the S5 Coupe. Among similarities are the body structure, market segment, starting price, ground shadow size, and height.