Difference between F and Z serial presidential? Was I duped?

[sdwtchlvr]

Geez that is a gorgeous watch. You're fine. Perfectly acceptable to have a watch like this sit at an AD for years before someone buying. True story: I saw an F serial 16570 Exp.II at an AD over xmas 2011. Doubt they've had it for 8 years...must have come from Rolex in more recent years.

[Onyx]

Originally Posted by SPACE-DWELLER

Good thinking with the clasp code, but actually that wasn't what I was thinking about... rather, I was thinking about the clasp style since around the F-series, the clasp was changed to the new style (as pictured above).

Here's an excellent summary of the Rolex Day-Date updates, written by Steva aka "Triple Black 88" in this other thread

The F serial does have an updated clasp over the one before (circa 2000-2001 model), I had both in my hand to compare yesterday. The clasp does look nicer, but not something anyone can see while you are wearing it anyway.