My '99 W210 estate has the 'power close' on the tailgate. Can't remember from the brochures at the time if it was standard or an option.
Frankly I fail to see the point of it on the tailgate - it just pulls the tailgate onto the catch but you still have to pull the tailgate down until its virtually shut, so why not go the added couple of centimetres??!! Besides its a guaranteed way to smash your rear screen if you happen to have a bulky load (e.g. wardrobe, garden bench etc.) inside that slightly protrudes beyond where the screen in the closed position rests. I doubt the power close will stop if it encounters resistance, and at least without power close you have the abilty to check the load and clearance without the risk of popping the screen!