Two Hatchbacks with some similarities, but otherwise different in most aspects such as the horsepower, fuel economy, market segment, ground shadow size, and height. First of all, the 2015 BMW 3 Series Gran Turismo has a more powerful engine and gets 59 mpg less than the 2016 Mercedes-Benz B-Class Electric Drive. Also, not only 2015 3 Series Gran Turismo is slightly larger, but it's also taller than the 2016 B-Class Electric Drive. Among similarities are the body structure, market segment, starting price, and maximum occupancy.