[bomber60015]

a great deal of typing and a fair amount of opinions . . . not bad, mind you, but light on facts, data, and information ;-}

I've had old helmet liners simply disintegrate -- granted, they were 10+ years old . . . but, given that the foam didn't loose it's energy absorbing properties literally overnight, they likely started to do so a couple of years before it fell to pieces . . . .

so, the question is, how LONG before, yes?

I have no idea, and I'm guessing you don't either --

If nothing else, the helmet comanies have a vested interest in selling product, for certain -- they also have a vested interest in their products working up to spec -- will a good quality lid work up to spec after 5 years?

I have no idea, and I'm guessing you don't either --

If you want to look for a conspiricy, ask yourself why the instructions on a bottle of shampoo tells you to do the whole thing twice.