i used 1 once,i thought it was a load of crap what was being said,but in the following 2 weeks a gas fire in my bedroom was strangely on along with my electric blanket when i came in from being out,i was sure i had turned them off before going out (was a really cold house),happened 3 times and after the 1st time i was very careful to make sure it was off.1 morning me and 2 friends were in the house and i demonstrated to them how to turn it off and how to light it,we went out together and locked my house door,came back together an hour later and the fire was on,nobody else apart from me and my mum had a key and she worked 11 miles away and wouldnt have came back and lit my fire then left.thats my experience,nothing happened after that ill add!!