American luxury-car buyers seem unconcerned with fuel efficiency. Why would they be? In countries where the gasoline price is three or four times that in the U.S., there is an understandable emphasis ...

Further solidifying its status as a legitimate competitor to the Mercedes-Benz S-Class, BMW 7 Series, and even more limited and niche models like the Maserati Quattroporte and Porsche Panamera, Jaguar ...