I'm running an AutoMeter electric and will buy one again. Easy install, easy calibration. I wouldn't consider a cable driven unit, and having to mess with trying to get the right drive and driven gears in the tranny to give you the right cable rpm at 60mph based on your rear gears and tire size. Electric is so much easier, and they can be re-calibrated in five minutes or less if you change tire size, or rear gears. My $0.02 and others may disagree.