It depends on the situation.
I'm a big fan of all types of bitted and bitless riding.
That being said, I really like:
-the myler wide-barrel comfort snaffle, for having a similar action to a french link without pinching or collapsing entirely, though my horse doesn't particularily like this mouthpiece.
-the kk snaffle, with the rotated center lozenge. The bit is also made of very nice material, and my horse goes well in this. I believe he likes the tongue contact.
-the neue schule verbidend bit. A nicely made french-link, from a nice material, with a nice tongue clearance 'channel' of sorts. My horse enjoys this bit too.
-the lg zaum bridle, a nice bitless option with minimal mechanical action.
-the lightrider bridle. My horse responds well to this one too.
Every horse and every situation is different. I don't ride western often, though if I did I would be exploring the comfort mouthpieces offered by myler, with shanks, or another similar independent side movement bit, or something with a wide, medium port to offer nice tongue clearance, both loose-jawed.
For any discipline, I think a standard, flat-noseband sidepull also has it's place.
A bit is an investment. They last a lifetime if not abused, and I'd like to treat those purchases as such. I know it's worth it to me to spend $100+ on a bit, knowing that I'll have it, and the option to have very clear communication with my horse, for years to come.
That said, one of the reasons I may think this way is because my horse had a tongue injury and is very picky about what he'll tolerate in his mouth!
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