The extensively freshened CLS gets a new 329-hp, twin-turbo 3.0-liter V6 hooked up to a seven-speed automatic for the base powertrain. The 550 gets a 402-hp, 4.7-liter twin-turbo V8 mated to a new nine-speed automatic. An AMG version with a 577-hp, 5.5-liter V8 delivers ferocious acceleration. Handling is capable and surprisingly agile for such a large car. The ride is firm but supple and steady. The coupelike styling results in a low roof and small windows, reducing interior space. That limits cabin access, hurts visibility, and compromises rear-seat room. Noise levels are hushed. Fit and finish is excellent, but the controls are complicated. All-wheel drive is available. This vehicle can be outfitted with a semi-autonomous driving package. Consumer Reports believes automakers should take stronger steps to ensure that vehicles with those systems are designed, deployed, and marketed safely. Please heed all warnings, and keep your hands on the wheel.

Alert
This vehicle can be outfitted with a semi-autonomous driving package. Consumer Reports believes automakers should take stronger steps to ensure that vehicles with those systems are designed, deployed, and marketed safely. Please heed all warnings, and keep your hands on the wheel.