Not very familiar with western bits BUT.. I can tell you this.
Bit 2 is different in the fact that it has a fixed mouth piece (which does not allow it to slide in the horses mouth) where bit 1 has a loose ring-type thing going on. Also bit 2 has copper there instead of steel.. That helps with acceptance of the bit. The bottom arm on bit 2 looks like it allows the reins to slip up or down depending on where your hands are more so than bit 1. And then, the obvious twist appears on bit 1.
Basically they are the same, with minor differences. The slow twist on bit 1 is more severe, clearly. All those little twisties do is create pressure points in the mouth, which I usually don't like, but some people (and horses) do.
Hope this helps.