I bought it online and have been using it on Butter for a week. It is realy wonderful. He was comfortable with it the moment he took it on. I can hold him still with one hand even if there is noisy puppy or running kids in front of him. There is basically no difference between walking in our quiet neighborbood or inside petsmart. A gentle tug on leash will correct him when he is walking too fast or is distracted.
In the beginner's training class, there are 2 puppies with head halters and 2 with easywalk harness, others are using plain collars. The easy of control is similar, but easywalk is way more comfortable. One of the puppy(yellow lab) has been using head halter for 6 weeks at least, and still is not comfortable with it and paws it all the time.