I've been using this for a few months, since for some reason my work Macbook really likes to crash when it goes into sleep mode (have a feeling it's related to our Vagrant/VMWare setup, but haven't had a chance to investigate). It works better than any similar tmux plugin I've tried, and is dead-simple to use.

I particularly like that there's a "whitelist" of which running commands it will restore, so I can e.g. restore both VIM sessions and my Webpack watchers when I restore my session.