Having been brought up on the 'yank and choke' method of dog training I would not recommend it for a novice owner - however I do feel there are still the very rare occasions where a check chain (note I say check and not choke) is the correct tool for the job. It needs to be used correctly - and I don't just mean put on the right way, you would be amazed how many people don't know its on wrong! It needs to be the correct length for the dog, put on correctly and kept up near the dogs ears to have any effect and used with a quick release action when the dog is walking properly. My preferrred collar is a half check, which gives you some control without the severity of the check chain used incorrectly. Obviously for a young dog it is preferable to not allow it to pull in the first place but for most dogs that turn up at dog training or have never been they are already past that stage. A Halti or Canny Collar can be useful but although they do stop the dog pulling they don't actually teach it not to pull and when you take them off the dog will still pull. A Harness in my opinion is not only a waste of space but can be very dangerous if used incorrectly, many dogs have had spinal problems because the owners yank the dog up in the middle of their back causing the spine to curve upwards. Harnesses were invented for horses (and sled dogs) to allow them to transfer the weight they are pulling to their shoulders and by the time a harness on a dog kicks in the front legs have already pulled so it is too late. Those very fine nylon harnesses cut into a dogs flesh and cause injuries. Mine are all taught to walk from a young age on a loose half check (often called a combi collar) and this goes for the tiny Heelers to the hefty great GSD. They need to be fitted correctly with the chain part forming a triangle when you put the slightest pressure on. This allows the handler to bring the dog back to their side and as they do so the chain makes a 'zip' noise and releases as soon as the dog is in the correct position. Used with titbits or toys they learn that it is a good place to be, and the handler praises them which is the best way to learn.