I would like to know if these very expensive helmets (about 500€) are actually better than regular ones. I'm sceptical about the claim that they are three times safer: if they are so much safer, why do they not seem to be being used by professionals? I cannot find any serious studies supporting these claims, so am wondering whether they are in fact substantiated.
That's the inflatable "airbag" helmet. It's main claim to fame is that it isn't really a helmet, but sits in a (dorky looking) collar around your neck until needed.
First off, I'm skeptical that the helmet could be tested to most bike helmet standards at all, since the test procedures would not be designed for such a helmet. So it's pretty much impossible to say if it "meets standards", much less is better than others. For helmet testing info smf.org/standards/b/b90astd (thanks to @Ken Hiatt)
Secondly, the trigger mechanism can't rely (as a car airbag does) on waiting until impact to activate. So it must trigger based on sudden movements of the head and upper body. The reliability of this is questionable. (Keep in mind that a substantial number of head injuries while cycling are due to simply falling off the bike -- the old "forgot to unclip" problem, eg.)
Third, given the iffy nature of the trigger mechanism, false triggering would seem likely, and having the helmet suddenly inflate in a critical situation could be extremely disorienting and lead to an accident that would not otherwise happen.
Bicycle helmets are all certified to the same standard, so I would be sceptical of claims that one is safer than another. With bicycle helmets, a higher price usually gets you helmet that:
As for the Hovding helmet specifically, it looks like the main selling point is that it sits around your neck while you are not actively colliding with something. Some people seem to think that conventional helmets look dorky and all helmets seem to give you "helmet hair" to one degree or another. So, I would say that this is again a case where you are paying to get a helmet that gives you more of categories 2 and 3 above.