Since I do not race on a course I have not changed over.
At risk of Hi-jacking the thread; I have changed my brake fluid after 8 years of using the original fluid. Actually I changed my brake fluid after 8 years and 13.4K miles. I was worried that a lot of sitting time could cause a break down of the brake fluid.
I also don't think that an occasional hard braking during spirited driving is enough to over heat the fluid and cause it to break down enough to warrant the use of a racing type brake fluid.