Two Sedans with some similarities, but otherwise different in most aspects such as the modifications, horsepower, fuel economy, model year, market segment, and ground shadow size. First of all, the 2014 C-Class Sedan C63 AMG has a more powerful engine and gets 16 mpg less than the 2016 GS 450h. Also, the GS 450h has a slightly larger body than the C-Class Sedan C63 AMG. Among similarities are the body structure, market segment, starting price, height, and maximum occupancy.