as long as the ski is stiff torsionally it will be fine on groomers. with wider skis this becomes more of an issue, unless you make the ski either stiffer or heavier, both of which are negative carachteristics to have in a park ski. so if you wanted somethig to ski park and groomers, i would go for around an 80-85 waist, it will hold better on ice due to the torsional stiffness, and it will be lighter to hit the park with.
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IAN
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