The best I got out of my old 140bhp Petrol (Auto) was 30mpg, the lowest was 25mpg and on my average travel to work ect I got 27mpg. On the over hand the 163bhp (5 speed Geartronic) the lowest was 34mpg, the highest was 49mpg but average day-to-day use it was 37mpg. If you hadn't guessed my day-to-day driving style isn't light and its a short 10miles to work so the engine is still cold, so high 30's or low 40's shouldn't be to hard to average. If I was in the market for a secondhand V70 and knowing what I do, I'd find a nice spec'd V70 D5 163bhp (5 speed Geartronic), yep if you step out of a petrol into a D5 you'll find it noisey but give it a few days and you won't notice it and mid range on the motorway it pulls great.