The standard G550 is powered by a 416-horsepower, 4.0L turbocharged V8. The high-performance AMG G63 is powered by a twin-turbo 5.5L V8 that makes 563 horsepower, making the big off-roader almost unnaturally quick. The AMG G65 is powered by a 6.0L twin-turbo V12 that produces 621 horsepower and 738 lb-feet of torque. All three engine options are mated to a 7-speed automatic transmission. Thanks to a serious mechanical 4-wheel-drive system, complemented by modern electronics, the G-Class has the goods for serious off-roading as well as simply taking on slippery road conditions. The system comes with three differential locks to distribute power in whatever way is best for the conditions. On- or off-road, traction is aided by the electronic stability control system, which also helps distribute power left to right. The G-Class is a truck-like SUV in look and feel, yet its interior is appointed with top-notch luxury materials, including premium leather, burl walnut trim and wood and leather trim elsewhere. Inside, the G-Class provides a very upright driving position that is different from that of any other vehicle from the brand's lineup. The rear seats even have enough room for adults, but they're not as easily reconfigurable for cargo when compared to most modern SUVs. Also, the back door is hinged on the side rather than the top. All G-Class models includes HID headlamps, rain-sensing wipers, front and rear fog lamps, 12-way adjustable heated and ventilated front seats, dynamic cruise control and dual-zone climate control. Mercedes' COMAND touchscreen audio control system is included as well. Safety features include mbrace2 emergency SOS that will automatically call for help in the event of an accident, blind-spot sensors, a back-up camera and a full suite of airbags for all occupants. Options include adjustable suspension, a rear-seat entertainment system and a heated steering wheel.