I really wouldn't reccomend mounting center on a low ski. People do do it, however it's not the normal thing to do. I'd just go reccomend if I were you, the JJ will be plenty playful on the line, an dead center would detract from your stability on those big lines you intend to ski. Even the most jibby oriented low skis, such as the EP pro aren't dead center mount skis, (reccomend on the OG EP Pros is -2.5 from dead center)
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Joey -Formerly *III.JVD.III*
I post from mobile the majority of the time, so if the above is incomprehensible, I apologize.