I was on that Anza Borrego trip with Casey and Safari Guard and was able to see the prototype in action. It is very stout, currently 2x2 steel, mounted just under the doors so they still open. Worked well, even as prototypes, even though the mounting behind the door did not run full length. I was assured the production model would do just that. It mounts to the existing body mounts underneath, similar to High Country's slider. I prefer the High Country for a couple of reasons...First, the High Country is 2x4, so it doubles as a side step for getting to the roof, etc. Second, the coating is truck bed liner, so it is easy to touch up scratches from rocks, etc. I think the 2x4 also keeps rocks further away from the door to protect it.
Of course, this is IMHO, and Safari Guard will make a great addition to accessories for LR3's, which will help all the manufacturers be competive.