Most other open graph plugins are incredibly bloated and try to add a bunch of other features. Not this one. I had it set up with my own custom image in no time, and the only footprint on the admin dashboard is an "Open Graph" link under Settings.
The only complaint as there are a couple of warnings created in the Open Graph Debugger if you include your "Facebook Page URL" in the settings.
See the warnings here: http://radleygh.com/images/chrome_2014-131-16-13-39-81.png
I'm not concerned about that, but hopefully it gets fixed.