Short bio: Computer Scientist, FOSS supporter (read more)
Tux Machines (TM)-specific
Though I use Ubuntu/Debian allied distros for my daily use, but one distro which intrigues me, is OpenSUSE. It has very stable distros and 8 months release cycle with on average each release supported for 18 months (for releases from 2011 onwards). Like Ubuntu excels in Gnome and Unity, OpenSUSE has excellent KDE version. In fact, if you are a KDE fan, I won't recommend you Kubuntu but rather request you to try out OpenSUSE KDE. I bet you'll really like it!
For 12.2 release, I downloaded both the Gnome and KDE versions. For virtualbox, I downloaded the 660 MB 32-bit versions. You can get the 64-bit versions here: Gnome, KDE.
Live-booting is almost similar for both Gnome & KDE. You are greeted with a Welcome screen and then the Linux kernel is booted. Live-booting is fast and effortless.