Howdy,
I would say the biggest part of bulls eye shooters using optics are shooting 3-4 M.O.A. dots. A 4 M.O.A. dot only covers 2" of the 8" of black on a B-6 50 yard target and only an inch at 25 yards.
The 7 M.O.A. and up dot sizes would have an edge in steel plate or other speed events.
Good luck
Mike