Two Sedans with more similarities, such as the body structure, market segment, starting price, ground shadow size, and height, than differences, like the horsepower, fuel economy, and maximum occupancy. First of all, the 2016 Audi RS 7 has a more powerful engine than the 2015 BMW ALPINA B6 Gran Coupe, and it gets 1 fewer mile on a gallon of fuel. And finally, you'll seat one more passenger in the 2015 ALPINA B6 Gran Coupe than in the 2016 RS 7. Among similarities are the body structure, market segment, starting price, ground shadow size, and height.