Regarding Elunevision's definition of opaque:
If you search the Elunevision threads you will find several references (including mine) to screen materials which they claim are opaque, but are not.
As Elunevision is apparently not interested in providing accurate opacity descriptions of their materials, it might be helpful if those of us with Elunevsion screens to post their exact screen materials and test for opacity.
I have the Vivid Pro Cinema White 2.4. Definitely not opaque. My screen has a TV and a mirror behind it. Plenty of light leaks through the screen, but not enough gets reflected back through to be visible.