I have flip down jacks on the back of my trailer (I think they are what you refer to as Atwood Jacks). Love 'em. I removed them from my tent trailer before I put it up for sale
and then took the jacks to a welder and had them welded onto the outside of the back bumper.
I considered having them welded underneath the trailer, but the prospect of crawling around on the ground (no doubt in rain) to flip them down didn't appeal to me. They flip up even with the bumper and are very easy to get at. They are also very easy to operate.
You can view a set at the following:
Another (cheaper) option is to go to an auto wrecker and get a couple of car jacks. Many styles are just like the scissor jacks.