I agree on max power and AO or parallax adjustment. When one is doing fine shooting on tiny targets like young ground squirrels, parallax can be a significant issue. I see no reason to give them any advantage what so ever.
My experience with the inexpensive Tasco's is that point of impact shifts with any change in power. Leave the power ring alone, however, and they are fine for the task.
Last edited by 1minute; 11/29/16.
