Thanks TeeJay!
My cold temp concern isn't about housing.

I am a professional backcountry snowboarder. I do research and development for a ski and snowboard company. My dogs snowboard with me. I am obliged to be out in the most inhospitable conditions possible to test equipment.

For example- I had a day in Dec.'07 when my climbing skins wouldn't stick to my bases. Essentially we were stranded until I could defrost the skin glue. It was -22F. My dogs curled up and took a nap in the snow while I defrosted my skins inside my jacket. I know that only dogs like my current ones will be comfortable under those conditions. They don't shiver even at -40F. I want a dog that doesn't need to be left home when I'm working.