Why LOL on the killflash?
I'm not seeing your point or reason for the tone of your post.
+1 There's a current thread talking about inbound glare and reduction methods, not to mention their use in not letting people beyond the muzzle see the red-tinted glint. There's even a comment hating on the killflash in the soldiersystems article, but I have not before today heard anything especially bad about them. Hell, I keep them on when I add a clipon to my systems so am not even worried about light transmission.