I spent big bucks on a grandpas feeder to reduce waste and optimize rodent control. Money totally wasted. After doing the training as instructed for a week, my chickens were basically starving because they were terrified of the movement of the feeder. I was shocked, as they are super smart and have caught on to using different style waterers, as well as being very adaptive to coop, pen, and tractor modifications. They are also very laid back.
Being metal, the feeder is very shiny and very noisy, both of which startle my Orpington hens. They are very suspicious of any device/container unless it is red, white, and glass/plastic. Note that they normally are not scared of noise from farm machinery, shouting, or barking. I think the combination of sudden movement and noise as the feeder opens is the main problem. However, they just generally did not trust it, rarely even stealing a peck of their favorite feed when I had it open. Also, I have to have feeders in 2 separate areas because I have 2 or 3 shy girls at the bottom of the pecking order that are scared to eat together with the whole group (9 hens). I removed the second hanging mason jar feeder during the training, thinking I could get them all to eat from one feeder, but they still would not eat from the grandpas feeder. No such luck. I know the concept of the grandpas feeder is great and many folks have had success with it, just not us

We are back to having 2 hanging feeders inside the run and the tractor.