So, hijacking the hijacked thread: It occurred to me that we do have some aluminum diamond plate to weigh for comparison
That's a fender from the trailer--less than 1/8" inch thick. Borrowing Shelly's dress makers tape, it seems to be 12 x 61.5 inches, or 5.125 square feet, and weighs in at 4 lbs 12.5 oz. If I did the math correctly, that puts it at 0.93 lbs/square foot, which compares to the 1/8 inch thick rubber diamond plate at 0.9 lbs/square foot. Pretty much the same weight.
Think the rubber still wins, since we can apply it to the slightly rounded cargo door, and hopefully wrap it around the 3/8 inch radius between the front and side of the teardrop.
BTW, I wish we'd had the option of getting black anodized aluminum diamond plate fenders. Not only will black fenders go with the rest of the black trim (doors and rubber diamond plate), but following Shelly and the empty trailer home in the evening, I was nearly blinded by the Sun's reflection. At some point, I plan to either buy new fenders, or anodize these.
Tom