as long as it`s a D or an O ring, you`re clear. Alot of hunt classes on`t allow the twisted bits but you can`t tell and everyone usually does it anyways. From a dressage point of view I will always recomend a french link O ring with platting of some sort, the softest bit possible. I don`t like happy mouths as they discourage salivation and hardening of the mouth but it seems to be the only thing that keeps my new mare happy as she has a very touchy mouth and loves to play at the bit.
If something is not to your liking, change your liking- the only thing you can count on in this world is change. ♥