Greatest invention for dogs that pull on leash

I've used this Holt Head Training Collar to walk our big grand pup, Ricky...a Texas Heeler (Aussie Heeler/Aussie Cattle Dog mix) for the last two days. It's made walking him so much easier and the walks significantly more pleasant. Prior to using this he would pull/drag me behind him as we walked or ran. Now, he wasn't too happy when I put it on for the first time yesterday...even fighting it, trying to get it off and nearly chewing through one of the straps; but after about 30 minutes of fighting it he I think he realized that he wasn't going to win. The first walk was jerky at first with him stopping every now and again to try to get the thing off, but after about a mile or so I think he just gave up. I allow him a couple of feet and if he tries to pull away a gentle tug on the leash that's attached to the head collar forces him to slow down and stop pulling. Now, I don't just walk him with this collar alone, I have a full harness on him and a second leash attached to that as a primary lead with the head collar and leash as a secondary control lead. It's working great and he barely fought it during today's walk. Best invention ever! Just wish I had thought of it sooner!