I use the two balls on a rope game to teach the out from a pup. I use "out" to get the dogs to drop toys or "out" a bite. I teach it with toys and proof it with a person in a sleeve or suit. It's all the same thing to me.
I do use "leave it" if the dog is going to pick up something it shouldn't. I also use "leave it" if the dog is about to pick up a toy I just told it to out. In sport or work, I have no issues with my dogs cleanly outing a suit, sleeve or a "live bite" if the suspect is relatively compliant. But, I rarely out my dog off a suspect that is not compliant or still combative.
One funny thing that I noticed yesterday was Boru, my new dog who is KNOV titled and trained in Dutch, dropped his toy when I said "out." It is progress as he was toy possessive and handler aggressive. I have been using "Los" with him, but Dutch is my third dog training language. My other dogs have always been English and / or German. Tonight, Boru was bringing his toy back, dropping it on the "out" and calmly allowing me to pick it up and continue the game. Sounds silly and trivial, but it is progress. I still haven't gotten bit yet, not hard at least.
"My biggest challenge is getting other people to use the words I use. I have used Ok for a release word, but I need to remember to use something else because people say Ok all the time in regular conversation and release my dog accidentally when I don't want to."
I use "OK" for a release, I had to remove that word from my vocabulary when I am working with my dogs. My dogs will not listen to anyone else, so that is not a problem. Your dog should be released by anyone but you, except maybe a family member. Certainly, not friends or strangers.