I bought a sample last year and haven't taken it out. For me, weight is more of a concern than size and these end up weighing about the same as a plastic decoy because the metal weight is heavy and it is not removable. So, there isn't a weight benefit over cheap plastic decoys, especially water keel. You could pack a ton in a boat, but they you would be spending an hour putting dozens of them together and taking them apart for storage. They would be hard to assemble with gloves on dark cold mornings.
Construction is fine, graphics are fine, they seem like they would last, but I just couldn't think of a situation where they would be what I reached for. Maybe some niche application.