I've had an iPaq (company issued) with Windows Mobile for 3 years now. I hate it.
Not only does it crash about once a month, requiring a hard reset and losing any unsynched data and losing any custom settings, but it refuses to sync with my PC about once a month, requiring a hard reset and losing any unsynched data and losing any custom settings. They put this God awful Credant software on them that turns half the memory into a "secure drive"--which also makes have the memory unusable. So I can't put anything worthwhile on now either. Not that that really matters, because the battery only lasts about 30 minutes off of the charger. Oh, and I actually have to have ActiveSync up and in focus for it to actually sync, being in the background or minimized won't cut it. It will say it's synched, but when you check the date for when it was last synchronized, I've found it can be a month or more!
But it does have a color screen.
I had a Palm V before this. It never crashed. It was easy to use. The battery would last about a week of heavy use without charging. I had to push a button to make it sync, but it synched every time I pushed the button. It never stopped recognizing my PC. They didn't put any crappy security software on it either.