Originally Posted by PiedmontBuckeye
I think the expensive ones just add some "bells & whistles" but not necessarily any more safety.
Absolutely, an example of this is shown in the SHARP ratings that the British government produces, where cheaper helmets have outscored much more expensive ones.
Part of the problem is that there is no objective definition of safe, so which helmet is the safest will depend on which tests you think most important.
The Snell Foundation's standards have been upheld as a marker of safety, particular in the U.S., but traditionally they have been incompatible with the U.N.'s ECE R22.05 standard, which is the legal requirement in almost all of Europe (including Russia) and accepted in many other countries around the world.
Snell required the ability to withstand a repeated impact, meaning a harder shell. The ECE favours a softer one so that it better dissipates the energy of an impact. So for any helmet it will be consider safe by one of those standards, and less safe by one of the others.
Any helmet that meets an appropriate legal standard is safe, after that the most important thing is that it fits properly and is in good condition.
When I was first started out riding I caught a patch of mud on a corner when I was wearing a cheap £35 helmet from discount supermarket chain Lidl that i had originally bought to have as a spare. I broke my elbow, but my head was fine. It was heavy and noisy, as reflected in the price, but it was safe.
I prefer system / flip helmets and used to wear a Caberg Duke which has a maximum five star SHARP ratings. But I did not think the ventilation was much good, and the field of view from the visor could have been better.
So when I replaced it I bought an HJC IS-MAX II, but it has just as many faults. Despite claiming to be especially designed for people who wear glasses, I have to take them off to put the helmet on, which was not the case with the Caberg, and it is longer so has to lay diagonally to fit in my top box.
The field of view is definitely much better but I am not sure the ventilation is any different. Both helmets had internal sun visors and came with a pinlock.
I am not sure what my next helmet will be, the other ones from recognized manufacturers in the same price range have lower SHARP ratings so it is likely to be one of those two again.
The HJC only has four stars from SHARP, but it has a 100% rate for the face guard remaining locked in their tests which is particularly reassuring. The Caberg was 87% so either of them is a compromise in one area.
Not everyone likes the SHARP ratings, in my experience a lot of those are people who have expensive helmets and do not like them not being the highest rated! But they have limited value as many models never get tested, and there is a delay after release for ones that are. I do not know how they pick which ones to rate, they literally just go out and buy them off the shelf.
But it is only a rating system and not a legal requirement, so it is good that the government just does any extra testing at all. More information is better than none.