Bench grinders are best for me when set up for a specific task. Baldor with two diamond wheels for precision on wood lathe tools, coarse wheels on old Milwaukee with coarse brush and one old b line with fine wheel and fine brush. Probably still need buffing wheels on another.
I think I paid about $400 for my long shaft 2 speed buffing machine. There are options out there for $100 for similar machines. I have never used one. If they have enough power and you don't use it much they might be worth looking into.
