Pepin
I participated in the Grafham Cat Open for the first time two years ago. It is a very congested patch of Water during the Event and "rules" are often ignored in the heat of the competition. There's a lot of shouting and bumping going on especially at the corners, so it only becomes fun once you have finished racing for the day with your boat in one piece. I must admit it was blowing around 20+kts when I was there so the runs were particularly exciting dodging in between 50-60 other racers. If my memory serves me correctly I believe the single handers started 2nd?
Anyway, it sounds as if there should be a good crowd of F16's this year and I should make it dependant on the prior weather forecast.