Friend of ours had a 2006 or 2007 CPO X5 with the 4.4 V8. Nice enough car to drive, plenty of power and I thought it looked decent. Holy electrical problems batman, they had all sorts of issues with the power windows, sunroof, lights, radio, climate control, sensors and the final nail in the coffin was that the engine started to knock and burn oil.......at 90,000Km of extremely thorough servicing and strict adherence to the manual. Nice enough car....no thank you because of the reliability.