After a couple of hours in marginal conditions the wind suddenly picked up and I had a really good 30 minutes of blasting on my biggest slalom board with the 7.2m.
Looking back at previous sessions on similar kit, I have added 2.5 knots to my peak speed and 2.2 knots to my 250m. All the more impressive because it was pretty darned choppy in places! I seem to be getting better at sailing in typical slalom conditions. :)
Tech Details: Navi GT-31 V1.2 (B1405x), GPSResults v6.63, Doppler, Cubic Spline.