Looks like a very well-executed design. Attachment options are a good thing. That firestarter loop on the outside face of the sheath is real different from most, which lay along either the spine or edge side of the sheath. That one looks kinda like something Buck Rogers would appreciate.
How snug is the Firesteel loop around the shank of the ferrocium rod? Reason I ask is that, with use, the firesteel will get skinnier and I wonder if it will get loose enough to either rattle or fall out.