Ok, I bought one too.....looked too interesting!!
I can't film myself for my cooking show without my glasses...due to having to see the Live View for focusing.
In my contacts, my farsightedness is hitting me...so, this way, I can use my contacts, and can use the diopter along with the magnification on the camera to now be able to view and focus for my set ups!!
I'll let ya'll know how it works out.
I got it for $120 shipped on Amazon.