As the title suggests if you were going to keep an X5 for a long time which model would you expect to be the most reliable mechanically over that time assuming that it is maintained via an old school methodology (oil changes at 5k, trans and diff at 30k, brake fluid and coolant 30k or every two years, etc.). Additionally, let's assume that the vehicle will be kept for 7-10 years.

Just so you know I am a long time BMW owner (e39 M5, e92 M3, e70 35d). The current diesel is going to be returned/sold at the end of its lease, this was really an experiment to see if I would like it and I do but I did not get adaptive drive and I really want it. So that means I will be ordering either a 50i or 35d in a few months.

At the end of the day I really am looking for the best long term solution. So let's have at the long term reliability, etc. while not discussing MPG.

Thanks.