Jay,
I don't know for sure if the body and cutter assembly has changed but the "new fluted carbide pilot" is new. The carbide pilots are $37.15 and the steel pilots are $9.00. I don't know if the solid carbide is worth the extra money or not. I'm not familiar with the dreaded dough-nut. I don't shoot competition, so is it worth it? I bought the steel pilot to do what I had to do. The steel pilots have worked for years. Maybe someone can clarify the dough-nut situation.
As for the old verses the new give K&M a call 717-292-3175. I think the "new" is referring to the carbide pilot.
Stan