You know my opinion, all boards will be fun to ride for sure
. Just since you really say its choppy (open water) do 2 slalomboards and one speed special for these 1 - 2 days per year you can break personal records.
The midboard is for me always the hardest decision, I liked iSonic 94 (2010) - iSonic 86 (2010) - Futura 93 (2011). The iSonic 86 was a step smaller when comparing these 3, and one time this was a benefit for me. Very very choppy water, small entrance course, gusts over 40kn. The iSonic 86 behaved very well with Reflex 6.2 for my 80kg and this resulted in a peak speed of 42kn
, that was the 2010 spotrecord (with strong contenders). I guess the iS94 or Futura 93 would be a tiny bit slower but still very competitive.
The iSonic 94 or Futura 93 however were like 10 next sessions (<30kn gusts) faster. Buying every board is not the best solution either (because we don't have all 24/7 to find windsurf trim). Conclusion was overall a 90 liter board would have more benefits for me in a 3 board quiver.
The big board 117 Wide and 107 are very very mean speedmachines
. I am lucky there is a 117 wide testmodel at the local shop, so I could try. I don't know the 117, but 117 wide was as fast as 107 till 20kn gusts (tested in choppy water) No big difference on GPS anyway. I remember doing twice the windspeed in 16-17kn gusts measured at 10m height with the local weather station.