I really liked the look of the soft rock guards on SmokelessJoe's gorgeous modernized Argosy24, so I asked him about them. He's been very happy with their performance and ease of installation and removal, so I contacted Hornsby Canvas, the company that made his, and had them make me a set for my Argosy. I really like being able to see all the way through my trailer while towing, and I like the light that comes in through the clear panos so I didn't really want the conventional Airstream rock guards, but I didn't want to crack a pano either. I just got the fasteners put on and here's my Argosy24 with the guards in place:
They seem a bit less smooth than his, but that may be because his are black so ripples don't show as much. Obviously they won't absorb as much of an impact as the smoke-tinted lexan ones, but the most likely highway impacts are smaller rocks kicked up by trucks, not yahoos dropping bricks from overpasses. They're made from Sunbrella canvas, with high-density foam sandwiched between the 2 layers of canvas. They attach with marine-style Common Sense stainless steel fasteners.
For storage (and possibly for camping on really hot Texas summer days) I'm planning to make a cover that goes side to side from Reflectix or something similar that attaches to the Common Sense fasteners.