With the addition of a new standard engine this year—a 2.0-liter turbocharged four-cylinder in the 528i—the 5-Series now gets better gas mileage than some boring mid-size sedans. Its EPA ratings, of up to 22 mpg city, 34 highway, with the eight-speed automatic, are superb.
The 535i is a good compromise for those who want more performance but don't have much tolerance for a guzzler. ratings for the turbo six are 20 or 21 mpg in the city, and 30 or 31 on the highway.
GranTurismo models might seem more practical, but their additional weight and height, and less effective aerodynamics, conspire to bring EPA ratings as low as 15 mpg city, 19 highway, for the 550i xDrive version of the GranTurismo. Although in all fairness, none of the V-8 550i models are very efficient, and the 550i xDrive sedan is nearly as low, at 15/20.