RE: iron sights
I use open sights most of the time. Off hand I go out to seventyfive yards or so, from a rest I would go 100 or a bit more. It is easy to check at the range. If you can keep your shots on the proverbial pie plate you are good to go.
This year I only had a two second opportunity at a deer, a doe fawn. It was off hand, 65 yards away at an angle away from me. I don't think that I would have found the deer with a scope in time for a shot but that is me. As it was, I hit in the center of the ribs and through to the opposite shoulder. I hit right where I was aiming. I rarely have an opportunity beyond 100 yards so I probably will not change unless my eyes do.
Bob