Just a note, I adjusted the BCS to come on "RIGHT NOW". Only took 5 minutes. It has made a significant improvement in throttle response and after three tank fulls of gas, I have experienced an increase in MPG of almost 1MPG. So far, no negatives.
I had mine set to "right now" but then back it out a bit because i can't get traction if i punch it from a stop/slow roll anyways so why do i want more power down there? I think it'* worth playing around with though to see what'* best for your setup.