I know this is not going to be a very popular response, but the truth is truth, even if nobody believes it.
These bags are dangerous. The fiber in batting and woven into the fabric is so fine that it is easily vaporized (a condition for combustion) and it does not contain enough moisture to prevent vaporization or extinguish combustion.
There, I said it. I'm a fire chief's daughter and I will probably still be acting like a fire chief's daughter the day I die. But, I won't die because I smoked in bed, plugged in a frayed cord, overloaded a circuit, used gasoline to start a barbecue or because I used a little quilt to cook my potatoes in.
