[Bear Guy]

I worked on getting start-stop technology into the automotive market 15 years ago, which is to say the technology is not new (been in production well over a decade). The trend started in Europe, to help meet emissions and mileage standards. The benefit - less fuel is used, as the engine does not idle when vehicle is not in motion. Engine restart times are measured in fractions of a second, such that restarts can occur as soon as the driver moves foot from brake to gas pedals.
Many manufacturers accomplish the start-stop function without engaging the starter motor, and so (depending on the make) there is no additional wear on the engine components. Users will also notice the start-stop doesn't self-activate under all conditions so that cabin comforts such as heat and a/c continue uninterrupted.