Take my feedback as just one data point. I am not sure if I am expecting too much from a car or if our experience is unique. My wife and I are relatively new to the BMW brand, bought X3 and X5 diesel new in 2011. My wife had 2001 RX300 was hesitant to switch from Lexus. I had a 2000 Toyota 4Runner 4x4 Limited. We bought both cars new. The Lexus ran flawlessly until the day we sold it. Had to replace the drive power door lock ($670). The 4Runner a bad coolant temperature sensor and had to replace the power antenna mast & motor a couple of times.
My X5 diesel has had 4 Check Engine errors and at least 2 recalls. My wife's X3 had at least 1 recall and 1 (maybe 2) Check Engine Light errors. Granted, her car was the first year so I am not surprised. Many of our friends drive BMW and seem surprisingly loyal given the issues that they experience which I thought was weird. One of our friends who had a gen 1 X3 said that she pays $1500 every year on mx and issues. She treats it as a given. I put up with the issues because of the way the car looks and drives. I never thought of my self as a car until I bought our BMWs. I still look forward to drive home in my X5 -- even after almost 2 years. I never felt that with our Lexus or Toyota. The 4Runner drove like a boat and the seats were extremely uncomfortable. Hope this information is what you were looking for.