It sees at night, prevents accidents, and leaves most sports cars in the dust: The ninth-generation Mercedes-Benz S-Class is more than a simple luxury upgrade. Its Brake Assist Plus system uses long- and short-range radar to anticipate and avoid collisionsor, at the very least, lessen the severity of a crashby automatically braking with full force if you don't stomp on the brake hard enough to stop in time. More impressive is the Night View Assist, which shines infrared beams down the road to illuminate hazards that are beyond the reach of the headlights.