This was using the just the seeall
https://youtu.be/yeSKD8g3FrQ
I've used it out to distance standing. Its kind of in my mind 50 and close. 25 yrds is to me my preference. But man sized at 50-80 is doable. Its all based on your skill and eyes. Its unmagnified. And as the guy said does cover the bottom of your view. But you lose that picture with other things as well. So it isn't a big deal to me. I dont bird hunt. I shoot slugs. And generally if i put the point of the triangle on something and pull the trigger the KSG will go BANG! And i see something down range go BOOM! So. Its a package that seems to work for me. I am not a super goodguy tacticool operator. If i can hit beer cans at a reasonable distance with the sight its good by me. In my opinion. 200-400 yards is something for a supersonic rifle round.
12ga can deliver a lot of foot pounds of energy up close but that round is heavy and not really leaving with a lot of speed compared to a rifle round. Its all a matter of what you are doing in my mind. If you got big open spaces or you got house to house spaces. Choose what fits. Or go with what you got. I see the KSG as semi urban combat and ground control defensive sort of weapon to be kept around with slugs. Car to car, house to house, the rounds with punch but can be accounted for as they are not ripping all around and covering big distances beyond the target. One of them rules of knowing your back drop settings.
The seeall is a fairly fast and easy sight to engage with like a reflex sight. With the triangle reticle you can quickly adjust your arc and level by seeing the with of the triangle and visualizing the tip on the target. For close in. You have a fast line up and can see your horizon line and know if your shooting low or high.
Ambient light seems to play on the styles. Normal daylight to some dawn and dusk but at night even with the trid nights you are a guessing game. Inside a building or house with general light it shows up okay. But i haven't gone all operator with it so i am sure for an average joe its in my opinion hands down a far better choice then flip up sights due to not having a bunch of parallax issues. You see the tip of the triangle at all. Thats where its going. Just like a red dot. But unlike a red dot.
I think the square set screw style is better then the pic rail slot kind. It secures tight. And doesn't have stuff to snag.
I also use them as backups on rifles over the flip up style.