Whats the difference with the canny collar we tried the halti and gentle leader on one of ours he hated it,we didnt give it long enough i suppose but he wouldnt come back to us after the walk as he knew it would be going back on, he then stopped coming to us during the walk just incase we were going to put it on and i wasnt prepared to spoil all the recall work we had done just to stop him pulling as he was off lead more than on it so more important that he came back when told. So for this reason i cant say whether they work or not as i didnt give them a good enough trial.