My arab is in a full cheek single jointed snaffle. She hates anything double jointed and I couldnt find anything else in the size she needs(little mare, small head) at the time.
I like to start them in full cheek snaffles, I also have several o rings, a french link loose ring in copper alot of horses seem to love and a very thin loose ring in sweet iron with copper inlay on my western bridle that every horse I put it on loves.
my favorite bits are low/medium or sweetwater ported bits with short swivel shanks
I find these very interesting and may try one in the future.
I cringe with some of the high port bits out there. For a very advanced horse and rider they can improve comunication, for most people that buy them they are a torture device.
Not a fan of thin twisted wire bits, tom thumbs, etc.