The hairline crack that I'd noticed in my VFD near the nipple, and that had me asking about spare VFDs recently, finally split completely. There is now a large chip taken out of the glass on the corner, and yet still, the glass is intact and not broken. Man, am I lucky, or what?

Barring accidents, and with a great deal of knocking on wood, I'd say that I don't need the spare I thought I was gonna need.