I think the key is to store the camper at a level similar to the rear of the truck (if possible) for the least amount of cranking?
My cordless drill struggles with raising the camper, so I do that by hand. Doesn't take all that long and it's good upper-body exercise ;-) But my camper isn't a "camp with it off the truck without base support" type - it's a 3-legger. And I don't camp all that often - a handful of weekends a year.
I see manual jacks as a plus in that the only "loss of power" in raising them is if I keel over....LOL!