I totally agree here with CPMcGraw on this one....go with the shock cord material.
I own two original Mars Landers plus an original unbuilt kit....the one that used the stock rubberbands now has collapsed legs...but it was built 20+ years ago.

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When in doubt, WHACK the GAS and DITCH the brake !!!

Yes, there is such a thing as NORMAL, if you have to ask what is "NORMAL" , you probably aren't !
Failure may not be an OPTION, but it is ALWAYS a POSSIBILITY.
ALL systems are GO for MAYHEM, CHAOS, TURMOIL, FIASCOS, and HAVOC !