I can't answer your question OP, but I'd really like to try going smartwatch-only some day.

The things I really need a phone for are directions, making calls, listening to music/podcasts, and occasionally replying to short messages. I should be able to do all of that from a smartwatch. Anything more in-depth can and should wait until I'm at a computer and ready to focus.

I would need the right product to come along, though, and that might never happen.