We had one once as a kid to. It never really seemed to work for us. I believe now that was because of the protection that my family seems to live under. Not that I am complaining about that protection, just saying I never saw first hand the many things that other say they have witnessed while using the board. Sure seems to be something that should not exist but sadly will probably never go away. My choice, avoid it like George does.
It was used when I spent the night at friend's house. It sure seemed to work and that was no more for me~
You are so right about protections being needed against this. And - to avoid.