Head Collars - Lots of questions

Have been advised to try using a head collar for Harry and like the look of the dogmatic. Any tips on how to get him to accept it please and has anyone had good results with a head collar? Is it likely to help with Harry's lunging and barking at other dogs and can they escape from a head collar? As you can probably guess I have never used one on my dogs, always relied on a harness.

These guys and girls have been using the Canny Collar but maybe worth reading through for some pointers:

https://staffy-bull-terrier.niceboard.com/t29570-maddie-and-her-new-canny-collar

https://staffy-bull-terrier.niceboard.com/t30098-buster-and-his-new-canny-collar

https://staffy-bull-terrier.niceboard.com/t29725-densil-and-his-canny-collar

I use a halti for Biscuit, and swear by them for the reactive dogs that I train with. I haven't ever used any other brands of head collars, but I know with the halti it has a clasp that does up just behind her ears and also a clip that goes onto her collar. She could probably get out of it if she REALLY wanted to but I also use a double ended lead (one clipped to her halti and one to her collar) she there's no escaping for her

It only took me about a week to desensitize her to her halti; if you read up about muzzle training online it's very similar to that. For the lunging and barking problem I do find that it gives me much more control, but I have also taught the "watch me" command which she has now almost mastered, so that when other dogs are walking past she now sits and focuses on me (and the treat in my hand) and allows the dog to pass. It took her a long time, plus impulse control training, to get her to this stage, but she was a severe rehabilitation case when I took her on, so hopefully your boy won't take quite as long! Would really recommend the head collar though! Good luck!