Do you know how to use them, and do you carry one with you just in case?
I'm just curious. My dog is a mutt, and I can easily get her jaws open with my hands. But she does have the hold/shake quality of a terrier. She's never been in a situation where I need to pry her mouth open except when she's chewing on toilet paper (I really don't know why she loves toilet paper so much); everything else a leave it or drop works with. But I do know how to use a break stick, just in case something happens and I need one.
I've been tempted to buy one and keep it in my purse after all the crimes going on here lately. I'm sure it'd work on a person's head pretty good :P