I have two Dell 1500 series, (one 1500, one 1501/digital+analog), and the newer one is a little crisper and faster, but not really by a huge margin.
They both have a very wide viewing angle, not as much as a monitor, but far better than the active matrix laptop screen I have, which is a good screen to boot.
The most noticeable is up and down though, rather than side to side, for instance, when I was wiring up the computer last night and sitting on the floor looking up at it on the desk, it was readable, but a little off. But that was a pretty extreme angle.
All in all, dekstop flat panels are MUCH better than any laptop screens I've seen.
Just be sure to get a newer one, like no older than two years, (even if it's new it could be an old model) because each newer generation seems to be faster and have a better viewing angle.