i have a F93 and F111 and F133 and just sold my F122. Sails 5.8 & 6.4 Naish red lines(3cam) V8's 7.0 ,7.5(for sale), 8.0 and 8.4RSS(sold). I'm 85kg. I've made some mistakes with the sail and board combo's. The 8.4 is to big for the 133, the 8.0 is great (so is the 7.5), 7.5 is to big for the 111, however the 7.0 is great (also the 6.4). The 6.4 and 5.8 are great for the 93 however the 7.0 is a bit to big.
It's not to say that you can't carry these slightly bigger sails, however i felt there is little advantage in it, even if you fin them correctly for the sail size.
I sail on the open ocean and very little on flat water, hence due to the rough water state a large sail seems clumbersome and doesn't give you any earlier planning. Seems to just bog it down. In flat water you can seem to get away with it a bit more.
Hope this helps