In my experience, these trucks are VERY reliable IF they have been properly cared for. My 2000 has been VERY reliable, to the point that we have taken it on every vacation (up to 800mi away-one way) since we bought it, even though we have a nicer, newer, better on gas car we could take (but I don't trust as much). We even pulled a camper to Silver Lake Michigan (sand dunes), beat on the truck in the dunes for a week, and pulled the camper home (roughly 600mi round trip). The only issues were a busted front lower valance from some rather reckless air time and a leaking front seal on the tranny from getting it WAY too hot pounding on it so hard on the sand. Lesson learned, installed a large trans cooler (in addition to the factory one) and a trans temp gauge. I hardly falt the truck for that though and it still got us home safely and without incident.
Unfortunately(or fortunately, depending on how you look at it), the resale on these trucks is VERY low, which means a lot of the time the are purchased by low income people who simply can't afford to keep things up properly. Add to that the fact that they are now 20+ years old and I'd expect to have to sort out a few 'bugs' when purchasing one. I'm actually in this boat right now. My 'ol reliable' is getting pretty rusty and I decided to replace it with another Expy (same year but better shape) because I not only love the vehicle but I have a great deal of faith in them. I bought the new one knowing I'd have to sort out some issues but I'm confident once I've taken care of that it'll be a solid, reliable vehicle again.