The Mercedes-AMG S65 Cabriolet is the top version of the new S-Class Cabriolet. That means a spacious four-seat cabin, a three-layer folding fabric roof, and all the bells and whistles. If the Mercedes-AMG S63 Cabriolet just has a 577-hp twin-turbo V-8 with all-wheel drive, S65 also means a 6.0-liter twin-turbocharged V12 engine made by hand in Mannheim, Germany, good for 630 horsepower and 738 pound-feet of torque.