I have had mine only a brief time, but:
- the window sticker, which has officially blessed ratings, says 94combined/37 on gas alone
- my car really does go 40 miles on a full charge. The dealer told me I might get "as few as 25 miles." But even with air on, driving to work about half on the Interstate ad 65 mph, and in the dark in the morning with the headlights on, I am averaging almost exactly 1 mile covered per 1 mile of estimated charge used.
- since I drive only about 36 miles per day, the motor almost never runs at all. I estimate my actual miles per gallon of gas bought at about 500. But that's not fair because the electricity costs a noticeable amount.
- I'm getting about 2.6 miles per kilowatt hour at about 11 cents per kilowatt hour so far, which, if one assumes the car would get its rated 37 mpg on gas, is equivalent to 87 cents per gallon. Turning that around, given gas is $3.42/gallon here, and I get 2.6 miles per 11 cents (4.23 cents per mile cost) can go 81 miles for $3.42 - so in my book the car gets 81 miles per (pocketbook equivalent) gallon.
'12 Volt, Ferrari F430 M6, Lincoln MKZ "Grandfather Car," Snapper 13 HP riding mower