Sometimes it's hard to explain why I use Emacs and not switch to other editors.
It's not that I have not tried other editors but I just don't see the point after looking at the feature list and the UI.
Every time a new editor comes out and someone talks up a new feature, it's either there in Emacs or someone quickly comes out with something similar.
Come to think of it, the complete integration of your work style either out of the box or through customisation is what keeps me with emacs. There is simply very little that you need to do or need a reason to step out of emacs.
Things that I find incredibly useful are
pcvs
ediff
org-mode
auctex
and a whole bunch of default settings in emacs. For a bad typist like me, the dabbrev and hippie expansion are a godsend. I mean, that alone saves hours of typing the same stuff over and over again.
Quite simply, I've come to the point where if an editor does not provide for easy integration with MY work style, I'd be quite reluctant to switch.
Am I saying I won't switch?
Quite the opposite, you better have something much, much better than what I have!