Honestly, I'd rather have an editor and assembler running on my system (probably WLA-DX and Emacs). But I can't deny this is impressive, and it's a nice primer for a system that I would love to learn to program.
I've had on my TODO list to integrate codemirror so other people can do everything remotely, but I don't think I'd use it myself. In principle it can be a bit faster to update, but a function key in Atom to rsync is pretty quick.
Do other people have positive/negative experiences with local/remote editing?