Hi Mate. I was on Maui when a lot of the testing was done on these sails. They work best with SDM masts only the 5.7 and 5.0 worked ok with RDM masts, still not as good as SDM. Is there a reason u want to use RDM masts?
Hi Kym How did the testing go. ? Another option to try is a tip extender it will soften the mast . We used them a lot on the old Hotsails that Bugs designed in NZ Terry