The 2014 Infiniti Q70's gas mileage ratings won't impress hybrid shoppers--or even fans of some of the greener V-6s on the market--but they're reasonable for a car of this size and performance level.
The rear-drive V-6-powered 2014 Q70 scores an EPA-rated 18 mpg city, 26 mpg highway, and 21 mpg combined. With the V-8, the rear-drive Q70 rates 16/24/19 mpg city/highway/combined.
In all-wheel-drive guise, the V-6 Q70 scores 17/24/20 mpg, while the V-8 rates 16/23/18 mpg city/highway/combined.
As a hybrid, the Q70's gas mileage improves substantially to 29 mpg city, 34 mpg highway, and 31 mpg combined.
All in all, the Infiniti M isn't a particularly efficient range when looking at the powerful conventionally powered models. Fortunately, there's the M35h hybrid, which scores 27 mpg city, 32 mpg highway, and 29 mpg combined, making a very attractive option in this luxury, performance, and size class.