I had the same problem. I bought a good quality boot, Lacrosse with I think 1500 grams insulation. Then I put on a pair of Woolrich wool socks. I put a toasty toe on each sock and then cover with an old pair of ragwool socks. My socks are loose and so are my boots. This combination has never let me down even in minus degree high wind weather sitting on the stand or in the snow. I have had hot feet when the temps get above 20. My problem was that my former boots didn't give my feet enough room to breathe. A boot 1 1/2 size too big is ideal for me.