I've made a few KTC bows.I think it's pretty decent wood myself.With design parameters along the same as red oak.Easily making a 50#@ 28" bow @ 1.75" wide.Even though the sapwood on KCT overall is thicker than osage or black locust I always removed the sapwood and used the heartwood.It could be leaving the sapwood would'nt hurt anything either.Takes heat treating well too.When heat treating it the wood will turn a lavendar or light purpleish color before turning brown.After finish is on and in time even the lavendar color will turn a light brown also.
I've sinewed them before too and they make very nice bows.