Great and easy to use
The structured data (on a page-attribute as well as global) was the key reason I purchased this but then found so many other nice little pieces of functionality that I really think this is a requirement for any C5 website with an SEO agenda.
Support has been extremely fast (even for problems that are with the C5 core and not directly with the add-on itself) so I can't ask for much more in this regard.
I'm just scratching the surface of this add-on and it's already become a must-have for each C5 project I commission here-forth.
Does what it has to do very well, also the support on the add-on is excellent
Also the developer serves excellent support. I wanted my page thumbnail to be the standard og:image. He helped me change all the lines needed in my theme package to get it working.