My two proverbial cents on the subject.
My average is 3.1 mi/kWhr/19" tires (over 24k miles driven so far), which my car should be very proud of. And that is with GT-P's peppiness/sheer power at hand.
I never watch efficiency, fcuk that, simply enjoying the car. I truly don't understand members here bitching about that. If one is worrying about it, buy Bolt/Volt/Niro/or some other "stuff". When I'm in Mexico (and in Mexico only) my speed on a freeway, Sprint mode, is between 80-95. The best part, at 95 or so, pressing the pedal still accelerates the car to an obscene speed.
Regardless, to each their own.