@matt: in the reviews for that trijicon a lot of people mention having issues seeing the dot when shooting from a darker area then the target. One said it was a problem in a indoor range, where the booth was dimly lit and target was bright, they had trouble seeing the dot. A totally passsive sight is a great idea, except it seems in that instance. Seems that electric sights may suffer from the same issue however as the photocell is mounted on the optic and is most likely not judging the light conditions down range. Have you had any adverse experiences with your passive sight?
I don’t shoot at indoor ranges, but unless they were pitch dark where you stand I don’t think it is an issue. Where the issue is most notable for me is standing in my dark basement looking out the window into bright day. Def less noticeable if you use a large dot vs one of the small ones.
That being said, it is a trade off & makes the argument for cowitness.