I can tell you the Sightmark Sunshade doesn't fit. The ARD will make less light pass through. It makes things darker, not dark, but darker, just enough. Depending on the where the light is in relation to you it is more noticeable. If you are not stalking human targets I think the ARD is overkill. I am still looking for sunshade that will fit.
All though, I have shot enough without it that it really doesn't matter. A sunshade will not help me make the shot.