I'm going to be living in a tent in the middle of nowhere in Arctic Siberia for a few days in january. Temperatures can drop to minus 50 centigrade or less and it caqn be extremely windy. I have enough gear to keep every part of my body warm, apart, possibly, from my legs. My question is the following: should i invest serious money in super warm pants such as Marmot 8000m or the Arctic bib pants from Northern Outfitters? Or will what I currently have be just as good: 2 layers of full length thermal underwear, a pair of cargo pants, a pair of padded pants and a pair of goretex waterproof pants on top?