
They are no replacement for proper time consuming training forging a bond of trust between you and your dog.
The only possible legitimate use for the devises, and that in expert hands would be for dogs that are in danger of being put to sleep for stock worrying, but even then it should really be a matter of ensuring the dog is not free to worry livestock.
There really is no shortcut to canine education, same as in humans, if there were an easy way we wouldn't have to go to school for so long.
Ask yourself would you put one on a baby/toddler?