A good friend of mine crashed an AS350 up in greenland 6 months ago(white out).He and his passenger had mustang survival suits on and survived after bee exposed to strong winds and temp down to -30C for several hours. He got very lucky on the other hand because he was in the middle of nowhere and a S61 passed overhead(IFR) and picked up there ELT.
Now when people complaine about clothing he give them a 1 hour lecture.