Grams of Insulation mean absolutely nothing with wet feet. I wear 800 gr, gortex boots coupled with polproplene liner socks and topped with different weight wool socks. If stand hunting in cold days (which during hunting season can get in the -30C range up here) I were in lighter boots for the walk and light clothing due to heating up/feet sweating. When at my location I switch everything over to dry footwear also makes sure my butt and feet are of the snow/frozen ground. Eat foots that provide sustained energy and drink only H20 never caffine which makes you void in turn dropping your core temperature. Lets not forget to keep the head, hands and kindney warm with appropriate clothing and measures. Blood flow important as well, small cirlce with the arms, winkling toes, etc. Boils down to more than one element for total comfort, miss one area and then you could have problems.