As soon as the isf-certified UHD 130 fabric became available, I got a replacement fabric for my frame. This makes the third fabric 1) the .8 gain grey that I used when I didn't have good light control, 2) the matte white 1.0 gain that I got when I was able to completely light control my room, and 3) the isf certified 4/8K 1.3 gain fabric that is now installed. This has been a learning experience for me. When one has a curved screen, as is mine, the experts on the AVS forum (including the owner of Stewart Screens), say that you must use a fabric with at least 1.3 gain. Why? Because with a curved screen, the uniform light dispersion given by matte 1.0 and lower screens causes light projected on one side of the screen to reflect to the other side of the screen. This is great for wide angle viewing but it causes a small amount of washout and will reduce the contrast ratio of the screen. A screen with gain reflects back more light than was projected on the screen and concentrates it in a narrower viewing angle. For instance, the matte white fabric still has almont 1.0 gain at 80 degrees to the side, while the 1.3 gain isf-certified fabric is down to .8 gain at just 60 degrees to the side. At an angle of 85 degrees, which would allow reflected light from the projected image to impinge on other parts of the screen, the gain is effectively zero.
Another benefit of the 1.3 gain screen is better reproduction of HDR, for which projectors are not nearly as good as direct-view TV's.
It took me an hour, from removing the screen to reinstalling it on the wall. The fabric fastening system is really easy to use.
Samsung UN75HU8550FXZA, SEK 3500 OCB in den, Sony XBR79X900B in LR, JVC RS600, Grandview 120" 1.3g curved screen in Batcave Mancave
Polk LSiM703 fronts, RTi-12 rears, LsiC and LSiM 706 centers, Monitor 40 Heights, Monitor 60 FW, ED A6t sides, Phillips BDP 7501 for small size,
Two Emotiva XPA-5's for the Beds and TC, BasX-7 for the tops, Marantz AV7702MKII in batcave. Oppo 203 in den.