Ubuntu user and not Debian but XFCE is awesome. It's my default environment after trying out Gnome 2, Gnome 3 (Shell), Unity, Cinnamon, KDE and whatever else I could get my hands on.
Eventually, after having a go with Xfce and finding it reasonably good, I tried the latest Kubuntu (12.04, KDE 4.8) and really love it. Every time I come across an annoyance[1], there's a checkbox somewhere to turn it off, or change it to work how I want.
[1] Annoyances for me include things like doing something just because I move the mouse somewhere - like showing an Exposé just because I put my mouse in the top-left corner.