The 2013 BMW 640i Coupe come with a turbocharged six-cylinder engine, and test drivers agree that it provides plenty of power. An eight-speed automatic transmission is standard in all 640i models, and reviewers write that it shifts rapidly and does an excellent job of finding the right gear. The 640i coupe gets an EPA-estimated 23/33 mpg city/highway, which is great for the class. All 6-Series models feature an adaptive suspension system, and auto writers say that it does an excellent job of delivering a comfortable ride and athletic handling. The 6-Series also wins points for its quick, precise steering, especially when outfitted with BMW’s optional Active Steering system.