I am a long time KDE user, who has switched his main production machine to fedora 11 and gnome 2.26, which, at the moment is much more stable than kde 4.2.4. I haven't tried kde 4 on fedora 11 yet, I don't think there is much difference between the different distros that run it. I hear the same complaints in the forums of all the different distros that use it.
My advice would be to get some live cd's that base their distros on kde and give them a try. PCLinuxOS just had a release today, I would figure that would be the one to go to first. Also, sidux just had a pre-release that contains kde 4.2.4 and was just released a few days ago, I still run sidux on a couple of machines, and they run as stable as kde 4 gets.
Don't get me wrong, kde 4 will be amazing one day, it just can't handle what I put my production machine through on a daily basis. Right now, Gnome can.