This. I tend to ride dead center on park specific skis, and 1.5 to 2 cm back of center for everything else. I'd mount cronics just back of center for an all around ski that rips in the park, or straight up center if your gonna ride mostly park. Basically:
all mountain with a few park laps----2 cm back of center/mid-sole
park with a few top to bottom laps----center/mid-sole