Two Convertibles with some similarities, but otherwise different in most aspects such as the starting price, horsepower, fuel economy, ground shadow size, and height. First of all, there is a $23,250 difference in the base MSRP. The 2019 Mercedes-Benz SL-Class has a higher starting price than the 2018 Alfa Romeo 4C Spider. Also, the 2019 SL-Class has a more powerful engine and gets 6.5 mpg less than the 2018 4C Spider. And finally, the 4C Spider body is significantly smaller than the SL-Class, and in addition to that, it's also slightly shorter. Among similarities are the body structure, market segment, and maximum occupancy.