The SL-Class benefitted from a total redesign in 2014, which included the extensive use of aluminum in the chassis. The end result is a lightweight body shell with outstanding rigidity and stiffness, with impressive performance all around. Though it mainly has a reputation for luxury, the Mercedes-Benz SL is a seriously fast car, no matter the model. The car is available as the SL550, SL63 AMG or SL65 AMG. The SL550 comes powered by a 4.7L, twin-turbocharged V8 that makes 429 horsepower and 516 ft-lb of torque. Paired with a 7-speed automatic, the engine propels the car from 0 to 60 mph in just 4.5 seconds. The SL63 AMG, is powered by a 5.5L twin-turbocharged V8, which makes 530 hp and 590 ft-lb. Finally, the SL63 AMG delivers 621 hp and 738 ft-lb of torque from its 6.0L twin-turbo V12. Mercedes-Benz claims a 3.9-second 0?60 mph time for its top-of-the-line SL, with a top speed of 186 mph. Of course, this wouldn't be a Mercedes-Benz without plenty of luxury and technology and the 2014 SLs do not disappoint. Mercedes-Benz has provided two versions of its convertible hard top -- a glass version and an optional "MAGIC SKY CONTROL" version. The MAGIC SKY CONTROL roof is able to change its transparency at the push of a button; going from transparent to opaque at the whim of the driver. The whole roof retracts in less than 20 seconds. The roof of the car is really just the tip of the impressive technology in the 2014 SL. Adaptive headlights swivel to see around corners. An automatic trunk requires no hands to open or close; a simple wave of a foot under the rear bumper suffices. Washer fluid is distributed through small channels in the windshield wiper blade itself, preventing any splashing and ensuring occupants stay dry even with the top down. The sound system utilizes empty spaces in the car's chassis to enhance bass. The emphasis on technology pays particularly large dividends when it comes to the safety of the SL. All manner of traction control, stability control and anti-lock brakes are standard. The 2014 SL also comes available with the Mercedes-Benz PRE-SAFE braking system, which will automatically apply the brakes if the car senses a collision. Two-stage airbags, including head and thorax, are also standards, along with a couple of rollover bars. Active head restraints also help prevent whiplash, and in fact Mercedes-Benz claims that the SL is the world's safest roadster.