Jacks are pretty much necessary, I think. We have a 15 footer and the thing wiggles around when I roll over in bed. Jack stabilize it wonderfully. I have held off, so far, on mounting scissor jacks (although it's on my wish list). I just use the four cheap aluminum pedestal jacks. They require more fiddling around than the scissor type, but they do the trick for now.
And hey, I can't sit still anyway, so I need something to fiddle with, even when I'm camping!
Enjoy the camper, we love ours and we just got it this spring.
Have fun!