I'd never use a bit that'd pinch or cause any pain. I'd use an unjointed snaffle (roll-bar center, so no pain caused), with rings that are built to prevent catching & pinching skin, or else put rubber pinch-guards on them, or have a D or egg-butt.
Copper inlay is far better than none, as well.
Stick to a good snaffle such as described, for horse's entire schooling. Horse shouldn't have to go to a harsher bit than this for any reason other than dangerous, do-or-die situations. People talk about the added "refinement" that a curb brings, but the curb is just a leverage device, like a can-opener, which controls the horse via pain.
With all due respect and kindness intended,
If you could just expose yourself to someone that approaches the various bits as a soft progression for the education of the horse you might change your mind some.
A solid bit is VERY
comfortable in some horses mouths and they enjoy packing the bit more than a broken mouth piece.
A person that grabs a plain ring snaffle and pulls with two hands collapses the bit inward and the bit breaks forward into the palate of the horse.
This is not how it is intended to be used ....but it happens every day.
As the horse learns the signals and cues from the curb,they can become very accepting and relaxed if it is introduced correctly.
Yes it can be used wrong,yes it can torture,yes it can over bend.
And the automobile causes 35,000 deaths each year in the United States.
I still am not giving up my truck.