Cadillac hopes the edgy and angled CT6 will help return the automaker to the realm of full-size luxury cars worth considering. The CT6 features an aluminum-intensive structure as well as high-tech goodies such as LED lighting, massaging seats, and a super-premium audio system. Powertrains include a 265-hp turbo four, a 335-hp V-6, or a 404-hp twin-turbo V-6—all with an eight-speed automatic transmission. The V-6 models have all-wheel drive; the four-cylinder has rear-wheel drive only.