 This is my 4th Bimmer, 2 530's, 1 325 - junk, and 1 X3 - junk... but the 530 is awesome.  No problems with 50K, just normal wear and tear but the front control bushings needed replacing at 20K, engine is solid and performs gutsy for an I6, the comfort has so many option that you can't go wrong and the feel is sporty but luxurious, tight, but comfortable, tight as you want it, with all the variations in the seat controls, and all the controls are also on the passenger seat.  After 2 yrs. I just found a new control for the back rest to tilt, huh, that was cool. I love the temp/ac/heat controls.  You can out the screen on ac and watch the ventilation automatically fluctuate, get one!