I know this is a controversial subject for a lot of people. However, from my own experience I have to conclude that e-collars are perfectly fine when used correctly. How many threads do we see on here about "door darting" and "escape artist" Basenjis that are impossible to easily catch if they accidentally get loose? How often is the advice given that you can't trust a Basenji off leash? My guy is infinitely safer because he is used to being off leash. When I have a "senior moment" (happens more frequently than I would like these days) and open the door for him without remembering his collar, he doesn't get all excited at his "freedom" because he is out loose 4 or 5 times every day. I just say "Perry, you forgot your collar" and he comes back so I can put it on. No drama, no adrenaline, and no escaped Basenji running down the road. He does not fear the collar, and he does not fear me. The rare occasions when he earns a rather stern correction (yes, it can produce a yelp of surprise and/or pain, I won't deny that), he isn't perturbed because the sensation is brief and it is over, and most of all, he knows why. Like my horses with their electric fence, he understands that his actions control the collar.
I do think that e-collars shouldn't be sold over the counter. I think a person should be required to take appropriate training before ever using one, because there certainly is room for abuse. But research has shown that a consistent, predictable cause and effect is not stressful to the animal. OTOH, inconsistency, regardless of the training method employed (yes, even "positive" methods) is very stressful, because the animal never knows where it stands. Anything can be abused. IMHO, too much crate time is the biggest issue for today's dogs that are left alone all day long while their owners are at work. Psychologically, this is a terrible fate for a pack animal…..