I could be wrong, but I think he is asking about the accuracy of the mils or moa's of the hash marks compared to optical ffp scopes, Is 1 mil really 1 mil?
The cr123 batteries are expensive so I bought a small rechargeable power bank to power the unit and did the 18650 mod for the light and now it's rechargeable also.
I bought a 4k mini from a member off of the classifieds several weeks ago and it does everything I need with the stock light out to 250 yards, love it.