As a longtime Vim user, I've been pleasantly surprised with the quality of Atom's Vim bindings. Text navigation and pane management bindings mostly work as expected. You get multiple registers for yanking etc. That's the extent of what you get, however. There's no emulation for the colon prompt, no macros, and it obviously doesn't support any Vim scripting.

I've been happy with Atom after transitioning from Vim, but there are still a few pain points. One that's particular annoying is that Atom's search/replace is very poor compared to the power I'm used to having with :%s.