Could you DM me a link for a reputable seller to watch? Idk how to tell who's reputable or not.
It's been too long since I bought a pen to be able to remember who it was I bought from, or to know who "the players" are in the pen re-selling market. But check the feedback on e-bay that's a good starting place.
Inferior to what? Surely not a Sailor 21K nail ...
Ooh ... this is gonna be better than "that's not a real P-51" ...