I've been using the Premium model for almost three weeks with the only issue being caused by the operator. I set up the system for light sensor plus 10 minutes, and one of my chickens didn't make it inside. When I tried to manually open the door, I punched the wrong button and had to recalibrate the system. Now that I've learned how the system works better, I haven't had a problem. I bought the Premium model with the self locking door straight from chickenguard.com. It came within days and was very easy to install. Just make sure you read the instructions. The Extreme model is for if you get a lot of snow, which is not a problem in Central Texas. So far, I'm loving this gadget.