That's the stuff. I used the Two Person Survival Blankets
for the tent. They're a little bigger and a lot lighter than the one you have.
I haven't seen one like yours yet, but I'd like to see what's different with it. With the added weight it's surely more durable. Have you noticed the shiny coating rubbing off?
This Escape Bivvy
is interesting too. I think someone here said they were thinking about giving it a try.
It might make a good bag liner, or if it's big enough, use it over your bag. I'd like to see one of those up close too.