Personally, I think they are stupid. What happens when sticks, rocks, and mud get into the hex voids? Not only could it stop you dead in your tracks on the trail, but it could create an unbalanced tire that is downright dangerous on the road.
Tweel as I recall. I think Michelin was toying with the concept originally. Mostly for industrial use. Lighter weight and more compliant than solids or foam filled tires. Could have its uses, but pretty cost preventative. I think they can be retreaded too which helps. Skid steers and lifts etc.
Personally, I think they are stupid. What happens when sticks, rocks, and mud get into the hex voids? Not only could it stop you dead in your tracks on the trail, but it could create an unbalanced tire that is downright dangerous on the road.