I think this is a great pet door for the price (half of what our local pet store is selling one of lesser quality for). A couple of things made me rate it 4 stars instead of 5. Firstly, it's not as easy to install as the girl on the YouTube video made it look, although it's easy to install once you get past the hard part of cutting through an insulated metal door. The other thing is that the three flaps and magnets make it pretty heavy and one of my dogs is reluctant to butt his head through it. Right now (July) I have the interior flap and the middle insulating one duct taped up in the open position so the dogs only have to go through one flap and they're fine with that. We'll see what happens when it gets colder, but I don't usually let them go in and out at will in the winter anyway. I'd recommend this door for both its value and usefulness.