I am learning how to rig my new to me 2005 Windwing Formula Race 10.0 and although the sail was tested on the GT mast I was thinking of buying the less expensive Fiberspar mast/boom combo. 

So much for Fiberspar as I have learned they have a completely different bend shape from GT.  Here is the snippet from the Windwing forum:

<<
Hi Pupo,

Yes 11.6 and 10.0 would be a good two sail combo. It also depends on your weight a little as well. If you are smaller and much lighter like 160lbs(72kgs) and below then a better combo might be 10.8 and 10.0. Unless you consistently sail in a place were it blows 8knots and under a lot.

I do strongly recommend the GT masts on the WindWing sails. Because they are very good masts and the sails were designed on them. But other masts that could work well also are NP's(although NP's have a big problem with breakage right now), also North's work well also. I reccommend agains the Ignition's and Fiberspars because the Gaastra sails have such different bend curves.

Best Regards

__________________
Devon Boulon
Chief Design Tester
WindWing R+D
>>
found at http://www.windwing.com/Forum/forum_posts.asp?TID=54&KW=formula+race+10&PN=0&TPN=3