Two Sedans with some similarities, but otherwise different in most aspects such as the modifications, starting price, fuel economy, horsepower, ground shadow size, height, and maximum occupancy. First of all, there is a $250,600 difference in the base MSRP. The 2017 Bentley Mulsanne Speed has a higher starting price than the 2017 Porsche Panamera. Also, the 2017 Mulsanne Speed has a more powerful engine than the 2017 Panamera, and it gets 9.1 fewer miles on a gallon of fuel. In addition, the Mulsanne Speed body is slightly larger than the Panamera, and in addition to that, it's also taller. And then, you'll seat one more passenger in the Bentley Mulsanne Speed than in the Porsche Panamera. Among similarities are the body structure and market segment.