IMHO I would vote for the AMK heatsheet. I have one in my go bag and I live in Florida where I am much more likely to encounter rainstorms vs. Freezing cold. The heatsheet can be used as an emergency poncho, great idea duckear I'll be adding that to my knowledge vault, and as a means of keeping warm. Living in Canada I'd think the likelyhood of requiring warmth would outweigh dry. Warm but wet equals uncomfortable, dry but cold still equals hypothermia.
Just my 2¢

-Bill Liptak