I would definitely recommend checking out the beta-tester plugin: https://wordpress.org/plugins/wordpress-beta-tester/
It gives you an easy way to check it out, and switching back to stable with it is simple from the interface by clicking “Re-install Now”
It will allow you to upgrade to the latest releases. It’s good to get a jump start on dev, but I would also say it’s a good idea to stick on stable once 4.4 comes out for the production side of things ( target date Dec. 8, 2015).