Something that is not mentioned much and can cost little. The use of old conveyer belts. These can be acquired generally for free from sand and gravel plants when they wear out. You can cut them to your liking in length (Generally 4' to 5'). I use a hole saw and cut random holes through the belt to allow for grip of the sand and mud for under side and tires on top. I cut about 33% of the total service area with holes. A smooth mat can slip if you get your wheels spinning.
My experience is you do not want the 4' wide belts but the 18" or 2' wide belts. I have been using them with the BLM at Glamis, California for the last 15 years and they work great in the sand and mud.
They are flexible for storage and have other uses, as a mat for the tent ladder, tent entrance or a shower mat.
They will not work as a ladder or bridge. Everything has its limits.
What I like about them in the sand, I attach a rope to it and the back of the vehicle, after I get moving I continue to a place where I can start easy (pointing down hill or hard pack sand) dragging the mats behind me. It is a lot better then walking back to get them.
I have used the X-Jack and had problems with the exhaust melting the fill hose. If the vehicle was cool and then you use it there was no problem with it. The problem is we are generally driving the vehicle just before we get stuck and it is hot. It worked good with proper placement I got tires off of the ground.
I am going to try this and I appreciate your posting it. Also thanks for your post about sand and dunes, I learned a lot that I wasn't aware of. Thanks again Frenchie