Solarmass I'm just used to GNOME. I've been using it for a few years now.
GNOME hasn't yet managed to piss me off enough to warrant switching to a different DE.
Also, my current install is nearly 2 years old and I really want to keep it going, and I don't like the idea of having 2 DEs installed.
If I ever do end up leaving GNOME (I'm not ruling out the possibility of it happening some day), I'd probably switch to Budgie or Plasma.