Oh man, that skidpad. This is PRICELESS for improving car control and confidence at various speeds, on or off aero. Finding the limit, going over it, upsetting the car's balance and recovering from it, drifting/slip angle practice, acceleration and braking in corners... I just spent about an hour going round in a couple cars, and it's EXACTLY what I was wishing for.
I am currently wondering if any improvements would be beneficial (custom timers, or speed or G averages; dedicated layouts for each radius, including or not AI support; etc.), but it's still a great tool as is.
cheers!