Okay, just to throw another option out there, which came to me as I read this thread, and looked at all the links you guys provided.
If you go with the Maxsa, you get 5½" wide and 23" long for ~$25. What I like about that is the joints, so you can put it down and climb out of a hole, if you are buried in sand. Try to put a
straight, hard traction mat in front of the rear tires if they are sunken, and you may not get them into position.
If you use Lynx Levelers, you get 8¼" x 82" of traction for about $30. Granted, the Lynx are not fastened together, but it seems like they may do a pretty good job in most situations, for less $$ (and I can tie them together if I really need to). Since I have 4 sets of Lynx already, I can throw the cubes in if I go off-road. I would not have thought about those, though, without this thread.
Lots of interesting products out there for situations we hope we don't encounter very often. We have to encounter them sometimes, though, to keep life interesting!