I didn't even know what a bosal was lol. I noticed no one has mentioned anything about the hackamore yet. All I have to say about that is, I think the snaffle would be better because the hackamores can actually cause more damage to the horse, if used improperly, than a bit. I say that because the horse has VERY fragile nasal bones that can break wayyyy easier than you think and the hackamore puts great pressure on the nasal area. Extreme hard pressure can do some major damage there. I'd stick with the snaffle for sure.