Just to let you know that my son is 9 and has worn one since he was just about 1 month old.  He has yet to be embarrassed by it although I can see how some children might possible be.  To him it’s just like wearing a bracelet.  Infact some kids do ask him what it is and he just says it’s his bracelet and leaves it at that.  He has only worn the bracelet so I can’t speak about the necklace but I can say that the necklace frightens me because of the potential for getting caught on something.  Not passing judgment on those who wear the necklace just something I think about.