Difficult day to go fast. Arrived early with no wind still took 5.8 waiting for the wind to fill in. Broke 1 batten and because wind was still light, went back to get 6.7. Off course wind increased and weird thing is I could not get the sail/fin/board combo working. It took me soo much effort to hit 70kmh. Spinouts all the time, strange enough I have used this set (at home @ salty waters) and it was flying. Just for the sake of it I took my broken 5.8 out again and it was working great. Too bad wind had dipped already, because now in little wind I could easy get 70's on the dial. Have to do some thinking about this day and I know one thing for sure, USM's are only a go for me if it is 5.8 weather :)..