Good insulator but....
Provides awesome insulation against cold snow. Can't feel the cold coming through it at all when camping on snow. Could save your life by insulating you from the ground. Got this to replace my lost z-rest. 2 problems though (almost dealbreakers) - 1. It's huge and hard to carry unless you are using a monster pack. I'd only use it with my 90 liter pack. 2nd problem is that it's like sleeping on concrete. After spending 2 nights on it on hard packed snow I've concluded that I can't sleep on this thing as I'm constantly tossing and turning every 10 min. Side sleepers forget about it. After laying on my side for a while my hip throbs in pain. Not good. From now on I will use this in combination with my inflatable pad. I can't ever spend another night on this torture device. I thought my z-rest was uncomfortable but this thing is a lot worse in that regard.