I would get them mounted true center. Measure tip to tail and find the center, and then mark it out clearly with a permanent marker. Also make an arrow that points forward on each ski, because shop techs have been known to mount stuff backwards.
Exact center sounds odd but last year was my first year ever riding park; and my season didn't start till like late January, and that's where my skis where mounted at. I absolutely love the way they ride (Salomon TwentyTwelves) They feel super good on rails and I've progressed super quick in the park (last year I couldnt even 50/50 a box... now I can at least fs/bs 270 out of a rail which is huge for me IMO and this season has barely started) I ride pretty much 100% park too, but during my lift hopping to get to the park, they ride and carve completely fine as well. I don't feel like much 'all mountain' performance has been sacrificed.
If you plan on ripping up a lot of groomers still, I'd maybe mount -1cm back from true center. Hope that helps! Good Luck!
secret fucking SNOWBALL mission...
Chaitea, "The best gloves are mittens."
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