I haven't seen it since I was a kid (a hell of a long time ago) but I used to love the humble people who'd turn up with, say, something Great Uncle Harry was given when he was butler to an Earl or whatever, and the look of shock on their face when they find out it's worth a small fortune. Maybe even better, though, are the really pompous folk who turn up with something they think is worth millions but it turns out to be something mediocre. I remember one old woman with a face that could sour milk and an attitude to match who was convinced she had an original Titian only to hear that it was a poor example of late school of. This pleased my twisted little mind.
I enjoy watching it on occasion, especially the British version. Pawn Stars can be good, too. My new fave, though, is Market Warriors! Full of fail, but lots of cool stuff.