Interesting, Ian.
I'm always intrigued by these things, but have so far been disappointed on the occasions when I've been drawn into dealing with them.
As a breed, Airless tires seem a Great Hope not always realized. The problem is, nothing quite matches the air spring of a conventional pneumatic tire. Substitutes might work pretty well initially, but tend to lose their hysteresis (wrt to rubberlike materials, their "bounciness") over time and become dead-feeling. No one wants them then, and switching back is not an easy task.
I have mounted similar tires for friends and neighbors and found the packaging includes an informal but compulsory language tutorial (one will learn to swear during the process). As difficult as it can be to mount any airless tire, removal after they've been on awhile is a descent to one of Dante's inner circles. Even a coarse-bladed hacksaw wielded diagonally is not enough to split the things asunder but is a great introduction to how tough they can be. Until every last particle is separated, they.will.not.come.off(!). 30in bolt cutters can nibble chunks from them but no more. A chop saw removes v-shaped sections but nothing more without involving the rim. Tire levers are useless to the removal process, and stabbing with a screwdriver is only partially successful in removing the outer layers. I finally took one to the local university and used a colleague's supply of liquid nitrogen to embrittle one of the tires enough to begin breaking chunks off it. Even then, it didn't shatter as I'd expected (hoped).
I really think the Next Big Thing in bicycle locks will be made from the carcasses of old airless tires.
Ah, me. In fairness, I have not tried these, so I must reserve specific judgement.
All the best,
Dan. (...who never tires of these discussions)