My 2007 X5 3.0si was the 2nd worst car I have ever owned (any my spouse and I are on about car 28 or maybe 30). While I cannot give details, it was SO bad BMW purchased it back from me. The electical problems were so numerous and severe...it was literally a nightmare.

Do yourself a favour, lease the 35d. The 3.0si is slow, and the X5 is a very heavy car. Also, mpg is not great in the 3.0, as the engine has to work very hard, due to the size and weight of the truck. I am beyond happy with my 35d. I feel obsessed with it