Friday or saturday, depends on what you want to do.
Friday has Flatwater Friday. I haven't been but I am going this year. There are some demo hulls and a lot of flatwater options. The beaches will also be packed with plenty of surf action.
Saturday is loaded with people. It's hard to find a safe place to ride. however, the raffles and any events like sickest trick are on Sat. Sat has the most people, the most skis and the most action. However, It is not the better day for riding because it's extremely crowded and the flatwater event is the day before. Additionally, There isn't many if any scheduled events this year. I liked the races and sickest trick and etc on sat but none of that is happening.
If I had my choice, and I was looking to ride surf and flat, I'd shoot for Friday. The core of the event is saturday, but other than getting up and getting one session as the 1st rider in the water, I don't ride on sat.
