I only started using it a few months ago. It's such a natural way to edit code, it only took me about a day for it to become reflexive.

Now it just feels vaguely annoying to work without it. It's fine, it's just one of those ergonomic changes that nags at you a bit. Kind of like the opposite of that feeling of taking off uncomfortable business clothes at the end of the day. Or what I imagine people who are better at vim than me keep talking about.