This.
You regulate the heat pads with a thermostat, which you need for the Flexwatt anyway. I don't like them because they act like there's no way it could ever burn your pet yet it's a very dodgy product. And Flexwatt's exponentially cheaper.
Maybe if we start asking for it? I mean, it's just the thing to put under my floors for winter heating, right? Oh, that would feel so nice...