I've been using PCLinuxOS (KDE) for three years on 4 machines, and have been happy with it. The rolling releases are great and usually work. There have been a couple of problems, but they're usually fixed in a week. The maintenance crew maintain an active and friendly prescence on their forum.
The distro is independent, not based on Debian or Ubuntu, so the occasional independent software may not have a plug-and-play distribution.