How did your dog react to a barking collar?

In a couple of weeks I will be moving into an apartment complex and taking my beautiful Mini Schnauzer with me. The problem is if he see’s anyone outside that window, if someone knocks on the door, comes in and he doesn’t recognize them, or anything out of the ordinary happens. He goes completely insane and starts barking one of the loudest barks I have ever heard. I know if he does this frequently our neighboors will complain (I wouldn’t blame them in the least) and nothing good can come out of that. So I have been thinking of getting him a barking collar. I do not want to do this to him at all, but I know we will have issues with the neighboors if I don’t.

Basically, I was wondering those of you who have a barking collar on your dog how did the dog react to it? Did they become traumatized by this? Did it solve the barking problem or did they become immune to the shock? Any information on this would be extremely helpful and appreciated!