I have a 3.0si, had it now for 9 months, and put 7000 miles on it. Early on my car developed a fault in the 4x4 system which is fully documented in this thread.
http://www.xoutpost.com/x5-e70-forum/...highlight=xena
However, other than that issue which was mildly frustrating, the car has performed flawlessly. I have found that it is a huge improvement over the E53 and echo many of the points made above. The ride is fantastic, the cabin more sumptious and the handling excellent (non-adaptive sports suspension). I have found the third row seat to be very usable with the kids, although it is tricky to use the seatbelts if only one of these seats are in use.
In the main the technology has worked pretty well for me. I did have an issue with the iDrive being slow, but found that it sped up when I changed the DVD from a DVD-RW to a DVD-R (I always use a back-up disc) - suspect the DVD-RW had a few bad sectors, rather than it being a DVD-RW per se. Phone with a nokia 6230i has been really reliable and clear, 12-speaker stereo system is great.
I have the standard seats with electrical adjustment and memory, and I have found them to be excellent on long and short drives - very comfy, although I think I will investigate comforts next time.
Fuel economy has been worse than the published figures (20.6 average versus 25.9 mpg per imperial gallon), but has been getting better.
Had one run-flat go on me, and it was not repairable - finding a 255/50 R19 runflat on a Sunday morning was impossible, so I now have a spare 211 style wheel which I keep in the garage.
Overall, pretty happy really, although I am sort of starting to think about when I will buy the SD........
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StumpyPete
Current: gone over to the dark side of Ingolstadt due to BMW unreliabilty
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