For anyone still having problems with double-up or double-down shifts, I highly recommend a simple modification to the stock Elite actuator from Lee Williams at WRD. Basically, the modification replaces the stock detent spring and ball bearing assembly with a much much stiffer spring and plunger assembly. This results in the actuator being much "stiffer" when shifting from one detent to the next.

I used to have occasional double-ups and double-downs (maybe 5 per average race weekend). Since installing the mod, I have not had a single double-up or double-down. Based on my math, I should have done over 2,150 shifts with the new mod (four full days of driving), and the actuator was great the entire time.

Jon