It can be a good bit on the right horse. I only used something like that on my finished show horse (in the Western events, of course). Posted via Mobile Device
A good bit is a bit that is balanced. A good bit is only as good as the hands that use it. If you are heavy handed No bit is a good bit. If your horse only uses a snaffle, then that is not a good bit. A bit does not make a horse better.
That bit has some positive attributes and some negative ones. I'm going to compare that bit apples-to-apples to other bits. I'm talking from here on out only about the interaction happening inside the horses mouth. Comparing the bit assuming the same rider with the same soft hands is riding. That's my disclaimer :P
The bit would only ever be OK for neck reining, direct reining would be too severe and unclear communication.
The high purchase is nice, the length of the bar from the mouth piece to the spot where the headstall connects. Purchases allow for pressure on the poll and helps relieve some pressure from shanks. So long purchase with short shanks makes a very nice bit. The other thing I like about the purchase is that it flares out a little, which helps not put unwanted pressure on their face.
This bit has pretty long shanks, but the higher purchase helps off-set that, still not enough for my preference, but well enough.
The high port provides a good deal of tongue relief, it wouldn't be ideal for a horse with a low pallet though, as the port may hit their pallet (which may of may not be desired).
The inverted curve on the shank also makes it a bit more intense, when it curves back in that allows for a lot of 'pre-cueing' where it only takes a tiny amount of rein to effect the movement of the bit.
There looks like there's a small amount of wiggle room for the mouthpiece, which can do a number of things. It doesn't seem big enough to make for any reasonable gag action, but may be enough for the horse to be able to relieve some pressure by moving it up on his own. But to me I'd be concerned about it pinching his lips.
There may be more, I'm curious to see what others say.
Sahara - you're right I didn't notice that the first time. Wow I really like that feature, even though I would never ever direct rein in a bit like that. But it's a good design, so it doesn't collapse like a snaffle type mouthpiece. I really like that. I would love that with a lower port and short rounded shanks.
I do no like correction mouthpieces. There are uch better options. You COULD direct rein in that bit but I wouldn't. By the mouthpiece and length of the shanks I would only use it on a finished horse.