I have a Bonehead which is great, but I have had (minor) problems with the audible port - the holes in the liner and helmet don't match up so unless you recut some of the liner you can't really hear your audible at freefall speed. I know of at least one other owner who had the same problem - he showed me how he had fixed his. This isn't really a reason not to buy this helmet - if you have the right shaped head it is incredibly comfortable, but it is an annoyance.