[exabrial]

Freaking cool, but maybe a slight projectile hazard?

[sparrish]

And likely beat the crap out of your undercarriage.

[tmoertel]

Related question: If the alignment of the rotating discs goes out, can these chains turn into undercarriage destroyers?

[Eddy_Viscosity2]

Looks like the tires causes them to rotate, they don't have motors. So if they aren't aligned and the chains can't get under the under the tires, then they won't spin and hit the undercarriage.

[Evidlo]

You'd probably hear the rattling and stop driving

[zeckalpha]

And rough on the pavement

[askvictor]

Possibly the opposite if they can be dis-engaged easily on sections without snow, where drivers would otherwise keep chains on

[zeckalpha]

I live in Minnesota which gets plenty of snow, and chains are banned on public roads.

[s1artibartfast]

Doesn't seem rougher than normal chains

[rtkwe]

Maybe slightly as the chain is slung under the tire so it's travelling faster than it would otherwise just being mounted onto the tire?

[chipsa]

The chain gets compressed between the tire and the ground. It can’t really have a much different speed than the tire itself.

[rtkwe]

I was thinking about the initial swing in.