Eh, Sublime's vim emulation is fairly terrible. There are a bunch of common commands missing, and it doesn't integrate well with some of Sublime's features.

For example, if you use tab-completion in insert mode, it records the action as what you actually typed rather than the completed text. So if you press . to repeat it somewhere else, it inserts the gibberish you actually typed. (And Sublime's fuzzy matching is really good, so that gibberish can be pretty bad...)