Have you any ideas where you want to rent from whilst in Tignes. Could you get in touch with one and find out what they have in stock / likely to have bought in for the new season ?
Ive always found it can be pot luck when it comes to rental stuff regardless of what you want.
You generally can get the right size but after that it down to chance unless find a really decent rental shop ( which obviously means you will be paying more to get the better boards)
You can also "demo" name brands at most mountains or big shops which is a more expensive term for "rental"
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