I had a red dot on my 870. It was fast. Was removed after a trip through the snow. Oops.
Just curious, but how do people co-witness? I find it to be the most confusing and busy sight picture. Why not just remove the red dot altogether if it breaks or runs out of batteries?
Red dots make targetting faster than with iron sights. Why bring iron sights into the mix again, and waste batteries? Am I missing something?