So I have run my regulator as a switch like your saying and the biggest problems were that you gotta keep switching it on and off all the time. And like Mike said, the overcharging causes problems. I drove like that for 3 months and smoked 2 batteries, and some other misc wires. Bubbled the water right out of the batts and melted one of em. My vote is to change it too a internally regulated one. Its a good helpfull upgrade, and easy!