mg seems almost, but not quite, entirely unlike emacs.
the thing that makes emacs emacs is not the keybindings or the so-called "modeless" editing (which is a misinterpretation by vim folks, emacs is way more modeful than vim), but the built-in scriptability / extensibility.
In my experience it highly depends on the editor. With Sublime Text 3 on OS X, each keystroke is delayed by SSHFS' latency. It's a pain.
Tramp transfers the files back and forth, always working on a local copy (if I remember correctly). It provides a better experience.
Some of the most frequent operations, like switching between buffers or windows takes 3 key strokes!
It can take more keystrokes than that, even, if you have three or more windows.
You can also cross compile it (which you cannot do to Emacs).
Microemacs and derivatives like MG or uemacs dates back to the mid 80's, and has been ported to pretty much any platform and OS you can think of (first time I came across one of them was on the Amiga in the late 80's), so they're practical if you want the same experience "everywhere", including places too limited to bog down with a full emacs, and when you don't want that experience to be vim.
I believe that Workbench 2+ for the Amiga came bundled with MicroEMACS, though!
And Nano is only an option for me to escape the horror of vi if I for some reason can't install an emacs-like.
Other than that I use Emacs variants in Common Lisp for programming. Mostly derivatives of Hemlock, an Emacs editor written in Common Lisp by CMU in the early 80s.
crontab -e
Select an editor: 4. /usr/bin/mg
A Forth REPL ?