Two Convertibles with some similarities, but otherwise different in most aspects such as the fuel economy, model year, starting price, horsepower, ground shadow size, and height. First of all, the 2016 Porsche 911 Convertible is priced $21,300 lower compared to the base MSRP of the 2014 BMW M6 Convertible, which is older by two model years. Also, the 2014 M6 Convertible has a more powerful engine than the 2016 911 Convertible, and it gets 5 fewer miles on a gallon of fuel. And finally, the M6 Convertible is both slightly larger and taller than the 911 Convertible. Among similarities are the body structure, market segment, and maximum occupancy.