I have a question who else uses snuggle safe (s) ?

http://www.snugglesafe.co.uk/heatpad.htm

I popped mine in the microwave this morning due to the expending storm that was 11 hours ago, I had rolled it up in a towel and the bloody thing is still at 88ºF !! The power never did go out but I was impressed with it ages ago but again it has amazed me. I have been working on a battery back up heat source but that is proving expensive complicated and is again on the back burner and there is a silly by law about running gas motors for too long so no Genny.