The magic of the pneumatic (air-filled) tire is that the entire air-filled space of the tire acts to absorb shock and vibration from the road surface. Airless

The magic of the pneumatic (air-filled) tire is that the entire air-filled space of the tire acts to absorb shock and vibration from the road surface. Airless tires give up this advantage, and only the tire structure between the wheel and contact patch are available to do the same work. The result is always a heavier tire that is a harsher ride. All the materials science in the world can't and won't find a solution to this. You can safely ignore any airless system for all but the most specialized applications.