Two of the most powerful production sedans on the planet size each other up in this head-2-head battle. Both the E63 AMG S and M5 Competition are powered by twin-turbocharged V8 engines, which produce similar amounts of power and torque. From the quarter-mile to the dyno and winding mountain roads, the all-wheel drive Mercedes and rear-wheel drive BMW are put through their paces to determine which one is the executive super-saloon of choice.
