David Lambeth had samples of these at the last UK HU meet. They did look good and the mounting system was particularly neat.
However, the versions that David was displaying had a good 5mm of rivet (the sharp-ish bit with the little ball in it) poking out into the inside of the box. These were all over the inside of the box, and on rough roads would cut/tear/hole just about anything you put inside.
To be fair, David said he'd mentioned this to MetalMule, who had promised to do something about it. However I would check before buying.
They did look strong and were quite light.
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