Chances are, if youve spent any significant amount of time with POSIX-compliant systems, youve made an effort to learn either emacs or vi. (Unless crontab -e shunts you to nano, and youve not moved on.) I suspect that those who stick with emacs are generally programmers, while those who stick with vi are generally sysadmins (although I do recognize that plenty of programmers spend their days in vi this is a hasty generalization made for the sake of argument). Since both editors are so different in approach, it makes sense to get deeply involved in one to the exclusion to the other. Being proficient in one is eventually more productive then only half-knowing both.

That said, I suggest learning both sets of keybindings.

The reason I suggest this is because many other programs implement either emacs or vi keybindings. By default, bash uses some emacs keybindings for moving around the command-line, although it can be configured to us vi-like bindings too. The aforementioned frankeneditor nano also has emacs-like bindings. Pagers such as more, less, and most utilize vi keybindings. As a systems administrator, at some point youre going to find yourself on an unfamiliar box, with a less than familiar tool. I guarantee that pulling the old I wonder if this tool uses vi commands for navigation trick will result in a percentage increase in productivity that, while completely cooked up off the top of my head, is nevertheless real and measurable.

So. If youve slavishly commited yourself to one editor and one set of keybindings to the exclusion of the other: Be Ye Not So Stupid.