I followed this guy's work. It explains which wire to cut. For me it does not trip any codes or immobilizer.
http://ecomodder.com/forum/showthrea...s-22602-4.html
The kill switch advantage will depend on speed and terrain. Driving through hilly areas is effective because on a long downhill slope you can kill it and coast, I do it at all speeds. EOCing in 0-50 mph speeds is also effective because the wind drag is smaller compared to inertial forces and you can coast for longer distances. anything above this speed and you will tend to decelerate to much to be effective. It takes practice to get a feel for the proper time to kill it.