What side reins are the best?

Could someone describe to me the mechanics of side reins?

• I was hoping to get some more opinions on side reins and how they work. In my opinion they put constant pressure on the horses mouth and the only way to get away from this pressure it to scrunch up the neck and get behind the bit causing the hind end to fall out behind. This is often mistaken for being on the bit because the horses head is down and their neck is rounded. So I'm asking people who use side reins: Why do you us them? And how do you think they work? And why not teach the horse about getting soft and engaging his hind while you're on him?

• Answer:

  If you don`t know how to use them, don`t ride with them unless you have a coach who knows side reins help you. Personal opinion, side reins and other tools are there to train your horse faster and easier. The less tools you use, the better of a rider you are. This is of course my personal opinion. I have never used side reins for the simple fact that I feel that its taking the lazy way out of training.