Shorter skis:
Better for learning balance
Better for learning spins
Better for carving short-radius turns
Longer skis:
Faster
Better for landing jumps (forgiving)
More versatile (all-mountain)
You pick.
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Demo days allow all skiers to try different skis to find out which ones reward their brand of poor technique.
"Pleeease! If I get into Ski Canada, then I'll be able to get a sponsorship, then my parents won't make me finish school."
- Marmot Basin local