when we went thru the 'why carry a spare' thread a couple of months ago it seems alot of the members rely on roadside services.
some plans have exclusions and may not enter private roads like campgrounds or gated communities or cover you on dirt roads.
My PW came with a scissor jack, I have roadside, but I know I'll be ok on my own as many of our travels are off the beaten path- dirt/gravel roads.
I also have a small 2 ton stashed underneath, and a piece of 4x4.
I'll test the jack every once in a while just to ensure the seals are holding and there is oil in it.
I sometimes will use a jack to steady the rig when parked, esp with the awning out so as to not stress the awning supports if the van rocks when we move around
Mike