It's a new plugin, so documentation is lacking at the moment. It will require a bit of SAML config knowledge if you want to get this up and running quickly. Having said that, ktbartholomew (developer) is super responsive, and will be able to help you get it up and running in no time! Once up and running, it works as expected. I have no issues recommending this plugin if you need SAML SSO for your WordPress blog.
Keep up the good work!