I'd rather have a sleeping bag and space blanket than the Hero Survival Bag
We recommend the Hero Survival Bag for emergency situations. It won't be comfortable but it will help keep you alive. Keeping them in the car or carried while you're outdoors is a precautionary measure.
Can you use the Hero Survival Bag in conjunction with a regular sleeping bag?
Yes, you can put the Hero Survival Bag around your normal sleeping bag to trap the heat in.