I regularly see people complaining about the "small window" of the RMR vs. other, less robust sights. I also see people asking which miniature red dot sight has the biggest window.
The window is only necessary to display the DOT. Nothing else. If the window bothers you (size, color/tint, shape) then you're doing it wrong.
What you should "see" is the dot on the target where you want the bullets to impact. Noticing, being aware of anything else to do with the sight is taking away from the whole idea of the sight.
I can tell you, absolutely, that when I raise the P07 up to put the dot on the target what I notice is where the dot is located on the target. Not what color it is, what size it is, what the window looks like, what size the window is, etc., etc., etc.
Taking time to notice the rest is taking time away from putting the bullets where you want them to go. Okay, I guess, for plinking, or some types of competition.
And, if they (Holosun and the guys that buy/use them) first prove them to be reliable I will definitely have one on my black P01 Omega at some point.