Due to all the issues with bushings and mandrels cause, I do all my turning, sanding and finishing between centers without bushings and measure components with calipers.
Never out of round.
No iron from the bushings get into the blank material.
No issues with bushing getting stuck on blanks ends when finishing with CA, etc.
No extra expense to purchase supplier bushings.
No 2 identical sets of components will measure exactly the same making any bushings useless.
Les