I used to have Ubuntu installed, but honestly, I never used it. It just took up HDD space. I also had XP installed too, but I never really used that anymore either.
I tried KDE4 out a while back though, and I found the entire effects to be glitchy, and it’s not like my video card couldn’t handle it (it was a 8800GTS 512 mb). Compiz-Fusion worked great under Ubuntu, so I just came to the conclusion that the effects in KDE4 were poorly written.
So, have the fixed the effects? I remember the minimizing/maximizing effect being extremely buggy. I probably won’t install Linux again until I get a new computer and make my current one a Linux box, but that won’t be until around 2011, after I had graduated from college.