I don't use a headcollar on any of my current dogs, but did use a Gentle Leader many years ago for my first rescue GSD, who wanted to kill all dogs that came anywhere near her!

I found it to be useful when I was out walking her but I don't think they get to the root of the problem - ie they manage a problem, rather than cure it. For some owners, that is absolutely fine as they just want to enjoy stress-free walks. However, I continued to train her on a check chain back then (going back about 14 years) and just used the Gentle Leader when I needed extra control out on walks.
None of my current dogs would need a headcollar, as I do spend quite a bit of time training them to walk on a loose lead, and they actually spend very little time on a lead at all as adults - due to where I live being so rural and quiet.
It sounds horrendous where you are Pam

I would hate to be concerned about loose dogs attacking me or mine every time we went out