I just switched from Kubuntu to OpenSUSE. I plan on writing a bit about my experience, but it occurs to me -- people may wonder why I went with OpenSUSE.
Well, the answer is because I've seen various reviews saying OpenSUSE is the best KDE-based distro -- so the question then becomes Why KDE?
I've preferred KDE over GNOME since about the KDE 2.x/GNOME 1.x era. And I think the bottom line is customizability.
I never much liked the look-and-feel of GNOME, not even in 2.x. The Apple-style system bar across the top of the screen without the Apple-style integrated menubar -- that's just wasted space.
But it could be worse. It could be GNOME 3.
I liked KDE3 better than 4, but 4 got to the point of being passable. Even if it's still missing basic functionality like being able to right-click on a launcher to change its shortcut settings. In fact the whole "Show a Launcher When Not Running" feature (an overly-verbose version of MacOS's "Keep in Dock" and Windows 7's "Pin to Taskbar") is pretty damn broken -- I can't get it to work at all with LibreOffice. (Well, I mean, I can get it to show a launcher. Just not one that works.)
So okay. It's pretty far from ideal. But XFCE and LXDE aren't exactly rolling in GUI-based configuration options, and the simpler WM's are worse still. So KDE it is, for now.