Minx goes in a loose ring, sweet iron jointed snaffle. The rings are ~5" in diameter and I would consider the bit fairly narrow. She LOVES this bit. She raced in a simple jointed snaffle, so I was worried that I would have control problems, but she's very rateable in this bit and responds well. I couple months back I tried her in a rubber (not jointed) Pellham and she HATED it. I think it was too thick. A few days ago I tried a kimberwick that had 2 joints and a copper roller in the middle and she was not pleased with that either. I do ride her bare back in a halter sometimes and she responds well, so I think she might be able to do a hackamore. She can get VERY racey in a ride situation though, so I'm not sure it would work at an endurance ride.Farley's favorite bit is a french link baucher (also called a drop cheek snaffle). I tried a bunch of different bits with Farley and figured out very quickly she cannot handle plate pressure that occurs with a single joint. She did OK with a narrow (when I say "narrow" in relation to a bit, I am referring to the diameter of the bars, not the width of the mouthpiece), solid pelham, but it wasn't "the one". She likes the french link baucher. she eats and drinks well with it, is rateable during rides, and is soft. Farley does NOT do well in just a halter (been there, tried that.....), however I rode her in a mechanical hackamore in the arena and she did OK. I might try her in one on the trail tomorrow. She's strong, but not racey during endurance rides, so it might work.
Both my horses do so well in a bit on the trail (no head tossing, eat and drink) I haven't had a lot of motivation to try anything different. I won't know the difference until I do try, so that's one of my goals this year is to see if my horses are even better in a hack!