Some brands here in Asia make a KW shafts specifically for breaking. Could be cored, maybe not. Not really looked into it. I have used my Hayakawa KW playing shaft to spread them, but only MR format. Used it both with original LBM ferrule, and the Melamine ferrule I replaced it with. Did a suitable job. Didn't feel anything other than slightly more flex than my Ignite G shaft. I wouldn't use it for breaking head on, more for the integrity of the wood joint than the shaft itself. I broke two or three of the Mezz DI shafts at the joint before I switched to ignite G.
