I always thought that you should use an abrasive that was softer than the particles. Visionary used soft particles on a lot of their balls, so I always used Scotch-brite pads. Using an abrasive that was harder than the particles would wear the particles down even with the surface and eliminate most of the advantage of using particles.
Some other companies used really hard particles like diamond so most other abrasives like sandpaper and Abralon pads would probably be okay for those, but I will let others who own those type respond.
I used a spinner with Scotch-brite on my Visionary balls but my spinner only has one speed. I did not notice any bad things, but I have slow ball speed so I probably would not notice as much as someone with normal or fast speed, and in fact, it may have helped me.
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