Some of you know that I was badly burned in a fire north of the Arctic Circle some years ago. I was trapped in the burning cabin wearing my longjohns...my WOOL longjohns. The only places on me that burned were the areas not covered by the wool longjohns.
HAD I BEEN WEARING POLYPRO, I WOULD HAVE DIED IN SECONDS! FIREMEN CALL THIS STUFF, "SHRINK WRAP"!
You can go on line and you can buy MERINO wool long johns that are totally itch free. They are WARMER than polypro. You can order online from New Zealand companies and get a mix of Wool and Possum (the Australian variety...not like our Opossum). SILK is also great and is very fire retardent. I wear a set of Silk longjohns and put the wool over them when it's really cold.
What are the odds that fire might be an issue for you? I don't know, but four of us found out in moments and one of us,WHO WAS WEARING SYNTHETIC FABRIC CLOTHING, died!
Polypro can really gather sweat and can stink in a hurry, too!
Wearing my combo, with tight weave wool over the top, Woolie Booger Handwarmer mitts, Bunny Boots, and a good wool Balaclava, I can sit at -40 degrees and have done it many times.
However, I prefer hunting in 85 degree weather in shorts and a tank top!
Too Short