I have an auto inflatable pfd and wouldn't go out yakking (or boating) without having it on.................. I can see surf launches where it isn't practical.
I think it would be an advantage if the yoke style self inflating life jackets had a crutch strap as they seem to come up around your neck quite a bit when inflated, I discovered this a month ago........first trip out on a yak, just out from the boat ramp with people watching, flipped it over, comments from boat owner was "mate, that's gotta suck eh", understatement I think lol...