Falling on M-snow and dendix is like falling on a cheesegrater, snowflex and powderpak actually have some cushion for you to fall on, they also have better glide and more closely mimic riding on real snow.
you can make a pretty fast setup with about 10 square feet of msnow. then just use turf or a plastic tarp on the landing. Also just check out the build a jib thread.