I have a few friends who own the 1988-1995 E34 5 series and they constantly have problems with them. But I also have one friend who has a '99 E39 530i with almost 150K on the odometer and has had ZERO problems with the car. Hope it helps. My information isn't very scientific but it seem like the e39 cars are far superior to and more reliable than the older e34 cars.
<span style='color:blue'><span style='font-size:14pt;line-height:100%'>Member of the Out of the Closet "I Listen to Metal and own a Bimmer" Club</span></span>