I have 17k miles on mine, it's avg about 14.5 mostly highway driving with an average speed of around 40 mph (which I believe is pretty high)

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2006 BMW X5 4.8is Lemans Blue/Beige/Dark Maple
-Nav, Comfort Seats, Heated Steering Wheel,
Rear Airbags, AUX Input
2009 BMW M3 Space Grey/Black/Carbon
-all options