what bmw should make you do when you buy an M car or one of their high-end sport v-8s (550 or 650) or their V-12 760 is include bmw performance driving school. this has benefits such as you're not moving from a suburban into a M5 without a little knowledge of what the car can do in your hands. plus, who wouldn't spend an extra thousand dollars for something that is worth while. When I bought my '06 4.8 I decided to do an M car break-in, which is 3200 miles before going above 100 or 4k rpm. During this time I went to the BMW driving school and drove a 4.8 on a track, knew what it could do before I drove mine the way "its ment to be driven". THis helped me out quite a bit especially since I was moving from a low power mercedes to a the x5. after getting track experience (albeit a very short time), in my case at least, you don't drive as fast, you are much more attentive, and the best part is that you know what your car can do, so there is no point in testing it. (this is in response to XX3's comment)

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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