Hi nyhunter89:
I am using the first version of Wildview EZ-Cam. I am using the twelve volt external plug coupled to a 12 volt 300 series Energizer battery. These are not as easy to move around as using the internal "C" batteries. I usually leave mine set up in a location for a good period of time, one to three or four months. I have had success taking pictures up to -30 degrees Fahrenheit. Mind you at this temperature you won't take as many pictures as in warmer weather. Animals do not move around as much when the weather gets extremely cold.
What ever model camera you decide on, try to get one with the 12 volt external port. If you have squirrels in your area, they love to chew on the wire to the external battery. I usually cut small branches and put over the wire to discourage them.
Hope this helps. Have a Happy Holiday.