Morane (aka momoFra59), 53 kg, is using her iSonic 76 with a Severne Code Red 5.6 in 15-20 knots wind :
http://www.star-board.com/forum/showthread.php?t=2849
as well as a Code Red 6.7 sail in lighter wind:
http://www.moranefra59.com/actu.html
Christine (62 kg) is using her iSonic 76 with North Warp 5.8 and 6.8 sails in 15-30 knots wind :
http://www.star-board.com/forum/showthread.php?t=2849
Drop her an email/PM or leave a post here in english if you need more assistance.
Cheers !
JM