Here is what happens to me when I use the Holosight...I am calling and all of a sudden a red will come running right at me...I have to find the fox in the red dot and by that time he knows I am there and he high tails it for the next county..Now if your calling and you see a red or gray working there way into your stand you can put the dot on them and pop them one...It's when they show up so fast and you have to find in the screen and then put the red dot on them...
Why not just use an illuminated bobber light styk right behind the bead of your shotgun..Attach it with adhesive Velcro...As soon as a fox show whether far or running right at you it's so simple to find it swing and fire...Cost of a battery type light styk is about $2.50 and it will last all hunting season..
I suppose if you do extensive practice with the Holosight type red dot and target practice at night...just do snap shooting etc etc etc you could master the red dot for fast incoming critters... However as you know and this IMO sometimes less technical works better when darkness sets in...
You can find these light styks in Cabelas, Gander, and sometimes Dicks Sporting Good and Even wal-Mart fishing bobber department.