Burgerville and McMenamin's in Oregon and Washington use Oregon Country Beef. It's just shy of being fully rated as organic and that's due to the pastures of the ranchers who make up the group not being able to guarantee the cattle's exposure to various herbicides. No Mad Cow risk with these guys!
http://www.burgerville.com
http://www.mcmenamins.com
If I'm in California, then it's In-N-Out all the way!
McDonald's and BK don't even come close in terms of quality. They're all about the cheap mass market stuff. I do like BK's onion rings though.
Rick