In the past, I'd always used full check collars. Currently, I'm using a half check on my cocker spaniel. Harnesses and retractable leashes are a joke, as you can neither control nor correct the dog. The ten-year old had no business using a full choke collar on that puppy without having been trained herself to use it properly. Not meaning to attack or offend anyone, but I don't think there's ever a reason to use prongs (typically for pullers) or e-collars (the police use them on their dogs). A "trainer" who has to use them is not much of a trainer. It's of the utmost importance that dogs are trained and socialized from puppyhood (8 wks. +) to behave, though I do understand people sometimes acquire their dogs as adults, adults that already come with a set of poor behaviors (such as my cocker). I learned clear back in the 80s from watching Matthew Margolis (Uncle Matty) that all dogs can be taught, that prongs and e-collars are unnecessary - even with difficult dogs, and that there's never an excuse to hit your dog. Remember his commercials? "LOVE, PRAISE, and AFFECTION". I also learned from him why treat training is so bad (a no-brainer, really). I've had to email him a couple of times when I was working with aggressive dogs - one fear aggressive, the other dominant aggressive. Though he's basically retired now, he called me right back, very nice, and more than happy to advise. Yes, I've watched Cesar Milan..... I know many people like him, so I'll just leave it at 'his way is not Uncle Matty's way'. Bottom line, if applied properly, the full check and half check will not harm a dog's throat, and they're effective.