According to Mercedes-Benz, the CLS-Class is a four-door coupe. The popularity of the CLS-Class has led to a handful of other luxury brands designing their own four-door coupe, including Porsche, BMW and Jaguar. Inside, the CLS offers comfortable and luxurious 2+2 seating. The CLS 65 AMG ups the ante with sport-tuned suspension and brakes, unique aerodynamic exterior modifications and 507 horsepower under the hood. The CLS-Class comes with a four-year/50,000-mile warranty and gets an estimated 18-21 mpg on the highway.