Two Sedans with more similarities, such as the body structure, market segment, ground shadow size, height, and maximum occupancy, than differences, like the modifications, starting price, horsepower, and fuel economy. First of all, there is a $26,600 difference in the base MSRP. The 2016 Maserati Quattroporte GTS has a higher starting price than the 2016 Audi S8. Also, a bigger engine usually means less mpg. But the 2016 S8 has a more powerful engine and it gets 1 more mpg than the 2016 Quattroporte GTS. Among similarities are the body structure, market segment, ground shadow size, height, and maximum occupancy.