I use a Coop Defender Gold but I do not live in an extremely cold climate. However, I do not think there would be a problem with it in those conditions.
I love mine. I have had it close to a year with no problems except for a small hiccup when I first got it. And, I still have not even had to change the batteries.
The initial problem I had was when the door closed it would get stuck in the tracks. It is like the tracks are just a little too tight fitting. I solved this by connecting a little extra weight with some metal washers. Then, it worked like a charm. There was someone else on here that had one and had the same problem. I told them what I did and they did the same and it worked for him as well. And, he was in a cold climate, Canada if remember correctly.