12705B has loft of 50mm w/ 50/50 horse hair while 12705 has loft of 57mm with 30/70 horse hair. That's a pretty big difference leading to the different experiences. I would rather try out the 12705B in your case but my 12705 has been rough so far.
That's not my experience at all with the 12705B, the white 50/50 fan shape horse hair brush. The loft is only 50mm and it's a fairly dense 24mm knot, how can that be floppy? White 50/50 horsehair is soft with minimal scritch.
Much more floppy would be the Vie-Long 04312 Cachurro horse hair brush. That is only a 21mm knot with a 65mm loft.
______Tall & Thin_____vs____Short & Chubby____
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