I'm not sold on the tradeoff, comfort-wise. The entering premise is that bike helmets are uncomfortable, but this collar doesn't seem any better. Seems like it would make you sweat, chafe, and would flop around during vigorous riding.
I'm very curious about how the accelerometers detect a tumble. Could vigorous riding trigger a false deployment?
Similar systems are used in Moto GP racing, and I think they have the bugs worked out, so the system can work as designed. But I'm not sure how a £400 product can have the same fidelity as the surely more expensive one for motorcycle racing.
An interesting product, but I'm not getting one. My $35 Bell helmet will continue to work fine for me. Plus, I don't have to recharge it.
tim