I have run autocross events with and without. Seems to work best with both on. The course I have been running is much faster and open then most parking lot events. We use an old airfeild the surface is old and exposed, very abressive, but fast even hit 3rd gear. With both systems on I do not get that much wheel spin and can just hammer thru the course pretty much redline in 2nd gear. I did a run after I turned both systems off. Spun the tires in 1st shifted to 2nd spun the tires till I finally had to ease off to get some traction. Ran into the slalom, everthing fine, about the 4th cone got on it a little to much, Bye bye 360".
I was cool out 55 or so and stock tires. Will try again when warmer.

 

... then you're not going fast enough