I'm an ice carver and I also snomachine and collect firewood. Warmth and durability are important to me because I can be either Ice carving at a windy -30 below or snowmaching through woods hitting branches and all sorts of jacket wreckers. I'm looking at the trilithium and tritronix 3-in-1s as well as the freedom insulated pants. I really like the orange for the tritronix (REI pic; NF pic is brown) and the outer shell seems great on the NFs. Shopping on the web I can't tell warmth when most reviews say "great warmth down to my low 20s". An Alaskan opinion on whether they will hold up to my conditions would be greatly appreciated.