So if I'm shooting a 4-12x40 at 20 yards or at 150 yards, I'm OK not to have the AO?
FALSE, in my experience, unless you always shoot with the scope set on 4 power.
In order to get the scope when set at 12 power to focus on the target at ANY range it is advantageous to have the AO. That is what my experience is. When set on 4 power, the AO isn't hardly needed. The reason i shoot a lot is because i enjoy shooting. If the 4x↔12x scope didn't have the AO, i wouldn't enjoy the shooting as much. ☺
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