A Google search for 'airless tire wheel' (no quotes) produced some more recent {articles | regurgitated press releases} and a video about someone else's response to the Super Tweel. ... but nothing for sale except forklift and bicycle tires.
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Polyurethane has been used to make faux spokes over steel wheels, but structurally, I'd worry about it in two situations: Driving anywhere in the US' southern half in summer, where pavement temperatures can get high, and driving in any mountainous region, where brake temperatures can get high.
The low end of the temperature range might be a problem, too. Even if the material doesn't fracture at low temperatures, its effective spring rate has to be different than at high temperatures, so NVH issues might be a problem.
</speculation>
I am sure that Michelin will be parading these around the OEM's - and that will be the first widespread application.
Word of Caution: Michelin was also responsible for the TRX and PAX. Both of those bit the dust and left a lot of folks with wheels for which the tires were not only difficult to obtain, but also expensive!
