I have a 2001 X5 4.4 (plus a 545 ‘04, R1100RT motorcycle, 325 ‘95) and love to drive the car. It performs nicely and rides like on tracks.
However the quality of some the components (window regulators, battery, electrical components, coolant leaks) used in this car are lacking the BMW luxury standard. Since the warranty expired I have been to the BMW service more than 6 times (in within 3week timeframe). It literally seems that the car (price tag $55k) is designed to fall apart at the end of the warranty period (mileage 56k).
What is worse is that BMW North America does not care.
The latter actually made me decide to get rid of my BMWs and switch to another Brand which cares about their customers.