I have never set up a WP installation to get automatic WP

I have never set up a WP installation to get automatic WP updates. I am very nervous about something breaking. In fact on one theme I did change to 3.8 and the theme broke. Not from you guys. But a premium theme. I got in touch and he instantly sent me a new zip. (The last install I did for a test site, I did do auto update and it just did for 3.8.1. Kind of nice to just have it done.) Wanted to know what is the best practice. Auto update or not?