Hellknight Signifer's with the Arcane Bond class ability can spend coin to make their special Signifer Mask into their Arcane Bond as a head slot item. however, since in PFS you can only use Arcane Bond for upgrades or existing items, and not for adding custom abilities, is there any point to doing this as a signifer? unless you were able to upgrade it from its mundane state to the equivalent of an existing magic item like helmet of underwater breathing, or jingasa of the fortunate soldier.
Any clarification?