So there you have it, an overview of a variety of common collars and harnesses. None is perfect. They are all just tools. But some are more likely to cause problems in your pet or may just provide a less than ideal match for your needs. In case you're wondering which I prefer—ideally my dog can walk on leash with the flat collar he wears regularly. But for those dogs that tend to pull and need more work, I tend to recommend a front-attaching harness or a head collar of some sort.
Once the dog loves putting his nose into the head halter and the owner puts it on, the owner may need to engage the dog in fun behaviors to distract him from the funny object on his face until the dog gets used to it.