Chronics will definitely be stronger in the park, but blends would be a lot better as an all mountain ski. If you're REALLY doing 50/50, I would say go for the blends for the rocker. There's less than a centimeter of width difference, so you shouldn't notice the difference in the park that much. You'll mainly notice that the blends are a little bit more playful and forgiving than the chronics, but at the same time you cant push them quite as hard, due to the soft flex and rocker.
You could also look at the new bacons if you're trying to get away from park a little more.
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