Two Convertibles with some similarities, but otherwise different in most aspects such as the modifications, horsepower, ground shadow size, height, and maximum occupancy. First of all, the 2015 BMW 2 Series Convertible M235i has a more powerful engine than the 2016 Mercedes-Benz SLK-Class. Also, the 2015 2 Series Convertible M235i is both slightly larger and taller than the 2016 SLK-Class. In addition, there is a difference in the number of passengers; the 2 Series Convertible M235i seats two more the SLK-Class. Among similarities are the body structure, market segment, starting price, and fuel economy.