Two Sedans with some similarities, but otherwise different in most aspects such as the modifications, starting price, horsepower, fuel economy, ground shadow size, and height. First of all, there is a $24,300 difference in the base MSRP. The 2016 Maserati Quattroporte GTS has a higher starting price than the 2016 BMW M6 Gran Coupe. Also, the 2016 M6 Gran Coupe has a more powerful engine and gets 1 mpg less than the 2016 Quattroporte GTS. In addition, the M6 Gran Coupe body is slightly smaller than the Quattroporte GTS, and in addition to that, it's also shorter. Among similarities are the body structure, market segment, and maximum occupancy.