Nobody answered for your question, thus maybe my answer will be helpful for you. I never ride on this sail, but last season I talked with Steve Allen and Wojtek Brzozowski about Reflex. They claim it is working perfect - you can adjust performance of sail for different winds and how it should reacting for gusts. Sailing overpowered is becoming safer and more effective.
But in my opinion (and many other nonprofessional windsurfers):
1. Sailor need experience with this adjustment to achieve effect of improved ride
2. You must be very experienced sailor If you need to have significant benefit from this.
After that talk I felt myself interested, but I'm not convinced that it is solution for me.
I hope my answer is helpful a little...