Choosing power-sanding accessories for bowls, and see that there are soft, medium and firm disc holders. Most of my bowls, especially now, will be big leaf maple, cherry and alder. Later, some madrone. Which would you recommend for these woods? I know some of you use your hands instead of the power sanding, but I think the wear and tear on my hands would be less with the power approach. The opposable-thumb part of biomechanics has little endurance these days.