I saw them demoed yesterday. I was very surprised by how relatively simple they appeared to be to route, drill, and install. I am not a hot and heavy domino user but I could see having the set for occasional use and even designing some furniture and other woodworking items incorporating the knockdown capabilities.
For instance I could see building a fireplace mantle in assemblies and then having the assemblies connected on site using the connectors. Would allow for greater efficiencies in some areas and would make moving a large mass of wood easier.
Now if I was doing a lot of knockdown fasteners then I would be looking at the other methods with their jigs and factor in all the costs and where the break even point was going to fall.
Peter