When looking into a well lit area, from a dim area, the dot can nearly disappear.
This is most noticeable when inside looking outside, at an indoor range with lane lighting in front of you, or when in a dim room and using a flashlight or looking towards a light source.
The benefit of the co-witnessed sighs is that even if it does wash out some, you still have iron sights there.
No ideas on the astigmatism question.
I have the -04 7moa orange dual illuminated, with about 500 rounds through it on my G35.
Last edited by MaximaDrvr; 04-29-2013 at 15:33..