There are quite few of the threads on auto pop doors as you mentioned and I think Ms rosemarythyme and myself are always involved in them
Mine is more about the convenience. I do not have the time, and really not the want, to even go down to the coop everyday. I go every few days to feed, water, clean poop trays, collect eggs and spend a bit of time with the ladies. They always have plenty tell tell me about every 3-4 days. I also check the complaint box while I am there just in case one of them needed to inform me of something that she rather the others didn't hear.
It is also a redundant security measure, but the pop door is inside a very secure run that is is more than adequate to handle the predators in my area. Bears here are very, very scarce and anything else it can handle.
I also have one that can be set by amount of light and time and I use the time setting. It runs off of AA batteries and I have had it 1 1/2 years and still have not had to change the batteries.
I'm satisfied with it.