Standard knurls work just fine in three wheel "nutcracker" type heand squeezed knurling tools so should be OK in that device.
I suspect a lever operated chuck will be better than a conventional key operated scroll one as giving more feel as to what is going on. cam ring operation rather than scroll would be better engineering but whether it matters in practice I know not.
Feeding and workpiece stability might be a problem. I'd mount it on the toolpost in the same manner as my Coventry die head and hand feed.
Don't really see the market. Price is comparable to, may be higher than, a cut knurling tool which is far better for industrial applications. Way to expensive for home shop guy or gal.
Clive