I have now owned my Coop tender doors(two of them) for a few months. I will add that the solar power system seems under powered. I bought 2 extra batteries from Amazon (cheaper and same physical size, voltage and mAh) to keep a battery with adequate power. Just now I had to open my manual door...
I have purchased two of the doors. This is my experience:
1) The door/s has not worked reliably for as much as 1 week. As this moment my chickens are stranded inside the coop. It took me an hour the last time this occurred to remove, troubleshoot and reinstall the door on the coop.
2)...