It really all depends on the horse, although if you are just starting him out a bit might be the way to go, for if you just break him in a hackamore, and later on find he nees a bit, he will know nothing about it and it will be just that much harder to teach him. If you plan on keeping him a stud, I would choose a bit for him, for they tend to be very playful and some end up being studish undersaddle as they grow and you wont have much control with just a hackamore.