By the way, to get back to the initial question of paint vs screen material -- I got a sample of Studiotek 130, which is basically the gold standard of screen materials. If I'm not mistaken it's around 4x the cost of Elite screens.
With the sample placed in the center of my screen, the RS-MM-LL is essentially a dead ringer for the Studiotek overall -- the ST130 sample completely disappears. Where the RS suffers is in terms of visible grain (i.e. it makes the picture look kind of "dirty" in solid areas, especially of lighter colors, and especially during camera pans) and viewing angle. The ST130 is totally smooth and texture/grain free, and has a wider viewing angle. When I put the ST130 right in the center of the screen, they are basically identical, but if I move it even a foot to the left or right, the RS brightness drops off and the ST130 is now noticeably brighter, with the effect increasing the farther from center.
The ST130 is brighter than the Glidden (as is the RS), but the Glidden has a slightly superior viewing angle to the ST and a significantly better viewing angle than the RS. The Glidden has no visible texture to my eye.
Now the above comments are with solid colors and test pattern, or stuff like cartoons or CG with pure solid areas of color; or something like the snowboarding movie Art of Flight with huge expanses of white snow.
In complex material, with lots of texture, color, detail, light, dark, maybe even film grain; or in mostly dark material, all of my materials -- RS-MM-LL, Glidden panel, Sherwin Williams panel, and ST130 fabric sample -- are for all practical purposes ENTIRELY indistinguishable from one another. And that's when they're literally overlaid on one another, side by side. If you actually had multiple full-size screens and switched from one to the other, I don't think you would notice any difference at all beyond the texture -- and even that is not visible in detailed and/or dark scenes. This, ultimately, is why I can't recommend the more expensive and/or finicky solutions. You may, depending on what you are projecting, be able to see a difference when they are literally side by side, but if someone switched out your screen when you weren't home, I think you would notice no difference in brightness or contrast, and would only notice (maybe) differences in grain/texture and viewing angle.
Note regarding texture: My RS is sprayed, the Sherwin-Williams and Glidden are rolled. Iirc, spraying is supposed to result in better, smoother texture, but rolling can result in a brighter screen. My Glidden has no visible texture or grain in the image from seating distance; the SW's is actually even smoother, but I get hot-spotting so I can't really say much about the SW -- no one else seems to have had any hot-spotting so maybe I got a bad batch? My RS produces distractingly visible grain/texture/whatever in solid areas, but again, this is not noticeable in regular detailed and/or dark content.
My screen is 10ft wide 2.35, and my sofa is about 9ft back. From the center seat on the sofa, the RS is noticeably brighter than the Glidden in the center of the screen. But even a foot or so off center, the Glidden panel is as bright, and beyond that, the Glidden is noticeably brighter, due to the gain dropoff on the RS. So with the RS, the center of the screen will be brighter than the sides, and people sitting in the other seats will see a dimmer image than someone in the middle.
The ST130 is great -- bright, smooth, and a better viewing angle than the RS -- but the price difference is so immense that it doesn't make sense to me for anyone who doesn't really have money to burn. You're paying hundreds and hundreds more -- maybe $1000 more -- for a bit more brightness than the Glidden, and the Glidden actually has less gain dropoff as the angle increases.