While I personally like XFCE (Xubuntu setup) as desktop, one should note that it also has some maturity issues still. For example there's the issue with disappearing panels or panel items: https://help.ubuntu.com/community/XubuntuPanels
And the apps aren't as full featured / as Gnome or KDE ones, which eventually forced me to move to another desktop, at least until XFCE matures more.
As most desktops allow changing the window manager, I eventually ended up selecting my desktop based on the apps that I use most: terminal, mail and photo manager . Bad experiences on other desktops with less used apps like CD/DVD burning affected this also.
So, I don't quite understand why people select desktop based on its window manager, or complain about one. They should complain if the desktop doesn't work with their favorite standards-compliant replacement window manager...
 Browser is of course one of the most used apps, but neither Firefox nor Chrome is tied to any desktop environment.