All of the open sources desktops have their strengths and weaknesses. KDE4 desktops do tend to look more like someone vomited widgets on them than "beautiful", which is a word I have seen used to describe KDE in the past. Some of the included applications are excellent, especially Amarok and K3B. I find simple things like syncing the calendar with Google calendar get a bit complicated. With the right configuration though, KDE can go like the proverbial brown stuff off a shovel, despite the accusations of bloat.
Gnome shell goes the other way. I think it looks nice, and for the short while I used it I got so used to throwing my mouse pointer to the top left for the dash that I started doing it on my Windows 7 PC at work. Downsides, performance of the window manager is terrible and the fact you can't turn the effects down to ease the issue is ridiculous. I understand that most of the basic feature require compositing so you can't just turn it off, but it's a shame they didn't create some better solution for this than fallback mode, which I tried for an hour and quickly abandoned it. I do like the fact I can enter my GMail username and password and have the calendar integrated automatically. If I were using a service not supported though, I can imagine that would be a pain.
I like Unity but it's not perfect, and I'm disappointed they removed the 2D version from 12.10.
I currently use XFCE. It's fairly lightweight, it sits somewhere between Gnome and KDE in terms of configuration options. I have Conky running on the desktop which I find far more useful, configurable, and better looking than KDE's widgets. You can search for applications using the Application finder. It's not as slick as the Unity or Gnome Shell dashes, but it is quicker.
I'll round that rant up by saying I'm happy we have the choice.