Really really good when used correctly
Can be helpful when used correctly
Most people should avoid them, but trainers and people with soft hands can use them correctly. If there is even a possibility that they would be bad for your horse, don't use them!
pointless & stupid. the force the head down & the horse always becomes reliant on them. they only put the horse in a false frame. you can achieve proper collection & a headset without them
It does destroy the neck of the horse and a lever tool to make a horse summit to pressure- you will only ever be riding the neck which has 7 vertebrae not the whole horse that has 54 - your horse would probably end up on forehand to try to release pressure- better off to avoid any short cut tools and look for why you need
Thought of using one in the first place
If they are used correctly they are a good training tool.
Personally I avoid them! People often use them as a quick fix. They easily encourage a horse to break their neck at the 3rd vertebrae which creates and unnatural head carriage and over tucking of the neck. This stretches the ligaments between the vertebrae at the top of the neck and cause cause the horse discomfort leading them to become sour when you ask them to go into a shape