Howcome you use so small fins for iSonics? My old Carve 145 had a fin size equal to the tail width = 52 cm as standard. On my new iSonic 122 (tail width 54 ) a 44 fin is considered quite big. Couldn't the 122 carry a 54 fin and the 111/133 a 50/57 fin for maximum power in marginal conditions with big sails? Maybe it wouldn't give max speed but planing and pointing could be a lot better.