Agree, although the Mutant Cell Pearl is far from a heavy oil ball.
To the OP, frankly, I'd be hard-pressed to say there's any "heavy oil" pearl ball, unless you took them down to 2000 or lower grit. A polished finish and heavy oil don't go together. So far, every pearlized ball with the big "high end" cores have been no more than medium oil balls, e.g., Mutant Cell Pearl, Anarchy.
However, like I said, you can dull the surface quite a bit and get a potentially decent look in medium-heavy conditions. Without that, they tend to be way too over/under.
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