Well, if I am right and the only purpose of the firmware update is to enable a web-based system reinstall.
No Mac that originally shipped with Lion or later would require a firmware update to enable Internet Recovery. See
OS X: About OS X Recovery.
Edit: I confused this thread with
Considering buying Apple Refurb June2012 MBP. (Or maybe it was
Monitor suddenly showing weird green lines.) In any event, ignore my post.
