With that information, I took all three hygrometers and placed them on the bottom of my new cabinet, about 6" off the floor of the humidor. After 48 hours they all read the same, 69% RH. Now, the part that gets me to believe that the beads are not as accurate as I'd thought, is that I have two pounds of 65% beads in a tray on the floor of the humidor, and they're still all white, none of them are soaking up any RH to bring things closer to 65% on the bottom of the cabinet.
Thoughts?