There is "VIntage Mode" for ST, but unfortunately it's not entirely accurate and also doesn't support some commands. VSCode's VIM plugin is more complete.

Self-plug: https://github.com/lunixbochs/actualvim uses NeoVIM to give you every Vim command/motion in Sublime, and some of the Vim UI (waiting on Sublime/Neovim changes for the rest). VSCodeVim is using it as a reference to drive part of their roadmap.

There's also the new Sublime Six which is very promising: http://www.sublimesix.com

Correct, I've got Vintageous installed, which is a more feature-complete implementation of VIM's keybindings and its "ex" mode.

It's still not exactly the same as using pure VIM, since some of the commands overlap with Sublime commands, and I tend to use a hybrid of both (for instance, Sublime's Ctrl-D command to make multiple cursors, which is incredibly useful when I'm editing HTML and have to wrap several lines in anchor tags).

Going into "pure VIM" is just to make sure I don't get too reliant on Sublime niceties, particularly as my day job requires spending a great deal of time SSH'd into random RHEL/CentOS boxes.

There's also https://github.com/NeoVintageous/NeoVintageous, which is a maintained fork of Vintageous with some things cleaned up, and some bugs fixed.