I wear Steger Mukluks when its cold enough. I have the Arctic double-wides. If it is at all wet out there are better choices. But if it will be in the 20s or colder there is nothing better.

I was ice fishing once in 20 below and my feet remained toasty standing around for 6 hours.

http://www.mukluks.com/

You learn something new everyday whether you want to or not.