I've used both Gnome and KDE based UI's, and yeah, I don't feel strongly about the differences, but also I've never felt like either one was actually good. They both get the job done, but they both feel designed by developers for developers, on the assumption that anything you can't figure out in the UI you'll Google or open a terminal and text editor to deal with it. Compared to, say, the iPad 2 which felt clearly designed for lay users down to the settings UI. (I feel like the later versions of iOS got more complex and harder to parse, so I'm picking the iteration I liked the most.)

But then again, it's Linux, I'm a developer, I'm used to Googling how to do things, and I play my video games on Windows, so 90%+ of my time in Linux is in the terminal, text editor (or IDE), and browser anyway. So no complaints - the presence of a fully featured UI isn't why I use Linux.