I don't think anyone actually has to have "used" them to figure out what they are. It's pretty darn simple to understand the concept... I mean, I'm capable of adding 2+2 and that's about the extent of brain power needed to see what these are about.
It is what it is. What do you want to know? Do they work? Sure, if you have the proper security pin. Which, by the way, it appears that for $19 I can purchase all of the security pins. That last part may have taken the brain power of 2x2...
But, like Hookup mentioned, if they want it... they'll take it.