One thing buyers/competitors may want to consider is that some of the sanctioned race/autocross events have contingency awards offered to competitiors competing on their name-brand products, such as certain tire brands... that could sway your choices if you want to try to cash-in on winning (1st place always, as well as typically 2nd place and sometimes 3rd place). This is not to say that the best products always win... the nut-behind-the-wheel (aka "driver") still makes the biggest difference at each event on any day.