[Sivik]

installing it is strictly personal security comfort... if you feel content with an alarm protecting your vehicle then your all set. if you want to make sure that can't "drive" you car away if someone tries to steal it, then install one. any car can have this done... its just tapping into a wire that every car will have. just a matter of determining the right wire.

now if the thieves wanted to "push" or "roll" your car away thats a different story, but unless they find this switch then the engine will not start period.

fuel cutoff switch has nothing to do with MPG. other factors determine MPG such as RPM, drag force, weight, etc... but thats not in this topic.

switch can be obtained at any local auto store... just a normal switch. hell, i even think wally-world sells them.

its a good idea if you live in a high theft area to have one, but if you car gets busted into there's no stopping them from jacking your interior up, but at least you'll still have your car.