I'd have to agree with Buddah.
I havent quite gotten up to the mileage per tank, he does!
I remember an old Top Gear episode, where they compared the fuel consumption of a Pirus and an M3, the point there is, its not so important WHAT you drive, but HOW you drive it.

My wife uses the Euro sometimes, it will always comes back with the fuel avg at 12-14L per 100K, I can maintain it around
9L, mind you Auckland traffic isnt that bad, even at peak times