I have been using Linux for almost 9 years now having started with Mandriva in 2004. I shortly afterwards switched to Ubuntu with Hoary Hedgehog and have been using Ubuntu as my primary operating system ever since.
In my time using Linux I have also become well acquainted with Fedora, Debian, and Linux Mint. Ubuntu has always been my favorite however and I have always preferred the simplicity and non-obtrusiveness of Gnome over KDE. I even appreciated it as more and more eyecandy entered Gnome with Compiz etc.
With the switch the Unity, I had begun being plagued with performance issues even when using an i7 with 6 gigs of RAM. My system just seemed sluggish and slow. I was hopeful with each release that it would get better but instead it seemed to get worse.
For quite some time I had been contemplating switching to another system or GUI but I couldn't settle anywhere. I tried Linux Mint but it did nothing for me and I was never crazy about how Gnome3 worked on Fedora. The simpler interfaces like LXDE or Xfce always seemed lacking to me for a modern desktop. Even though I was bothered by Unity I still felt that as a whole Ubuntu was the best put together Linux distro with great support.
I came to the point where I got so fed up with Unity's sluggishness that I even considered switching to a Mac as my next computer
I finally decided to take another shot at using KDE. I had never been a fan of it in the past always finding it a bit clunky and un-elegant but after installing Kubuntu 12.10 and customizing it to my liking I am enjoying my Linux desktop more then ever. KDE 4 has become a polished elegant and highly customizable modern GUI. It is far quicker, more responsive and more fluid than any Desktop I have used recently, and it comes with some highly productive tools and utilities.
I am pleased to say that after almost leaving Ubuntu after 9 years, I will continue being a member of the Ubuntu community with Kubuntu 12.10.