It depends on the grit at which you sanded it. I've had one for years and tried many different surfaces. If its polished now, take it down slowly, not in big steps.
Although, in my opinion, that ball works better with some sort of polish rather than sanded. Sanding this ball will make it roll out to soon. When you sand this ball, regardless of the grit, it will not store energy as well. Which will make it hit weaker.
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Columbia: Wrath - Ti BossII Pearl- Gold Pearl Quake - Chaos
Hammer: Doom - 3D Offset - Vibe(B)