I personally wouldnt worry too much about flexwatt as the amount of people and years it's been used vs how many incidents of fire that were product error are probably pretty slim. If you are really worried, Flexwatt now makes a fire retardant version of Flexwatt. Havent tried it as i just use normal on all my cage stacks. Does kind of make me wonder if they are just improving on their design with the times or if they think there is a problem with it haha. J/K, I'm betting they are just upgrading it as any other product does after so many years.