Not the speed-day I was looking for. I still experience that these modern slalom boards don't work well on flat water (logical if you know that they are build for high wind slalom). Also tried the JP Speed 54 but this was too small.
Did some slalom sailing and some speed runs in between. In the end switched to JP71 and did some intersting testing together with my dad, was fun!! I even did my 5th fastest run, and best 500m, with the big board in dying winds.