The Mercedes S550 is a standout leader in quality and elegance, and has a backseat with every amenity possible to provide extra comfort to travelers. The backseat recline feature allows for many different lumbar positions and the massage function makes long trips extra relaxing. The S550 has a 4.7-liter, twin-turbo charged V8 engine with electronic stability for a powerful and smooth ride, and the tinted windows have infrared-reflective glass to reduce noise and heat.