Bigger, faster, and more luxurious, the new S-class plays it safe with evolutionary styling and a host of collision anticipation and avoidance systems. A spinning joystick--similar to BMW's reviled iDrive but slightly less confusing--operates the stereo, climate control, and navigation systems using a large screen to the right of the gauge cluster. Metal-look buttons, liberal wood and chrome, and indirect lighting give the cabin a modern and airy feel, and interior dimensions rise one to two inches in all directions. A panorama roof and a rear-seat entertainment system are optional. The available Brake Assist Plus system monitors closing speed and distance to cars ahead and increases brake force to avoid a collision, and the Distronic Plus adaptive cruise control now can bring the car to a halt if traffic ahead stops. Braking is handled by a conventional hydraulic system; the troublesome brake-by-wire system on other Mercedes model ranges will die when those cars are replaced. The S550 bows in January with a 5.5-liter V-8 making 388 hp and 391 lb-ft of torque, a seven-speed manu-matic, and rear- or, a few months later, all-wheel drive. The S600 arrives this spring with a biturbo V-12 sending 517 hp and 612 lb-ft through a five-speed transmission to the rear wheels. Later in 2006, watch for a base model with a smaller V-8 as well as an AMG version with more than 500 hp from its normally aspirated, 6.2-liter V-8. There's no word yet on a successor to the outrageous 604-hp S65 AMG.