Well first of all, congratulations on your first pair of Oakley's. The X-Metal is the best, in my opinion, to start off with.
That's quite common, my first pair is also the Juliet. But mine didn't start to flake after a few years, and I wore them frequently. Whoever had them probably didn't store them right? Moisture with friction will cause them to flake quicker. I have a bunch of those silica gel pouches to put inside the soft vault when I'm not wearing my Juliets because the humidity in Los Angeles can be gnarly sometimes.
Thanks for everyone's input - I ended up getting some Prizm Black lenses cut by @Chris A Hardaway. (Thanks Chris!) I'm not a collector, so this is probably the best approach for me rather than sourcing OEM lenses (which are probably hard to find and subject to the same peeling issue). I like that they look similar while providing the contrast of the Prizm lenses.
Here's a pic of the lenses. Prizm Black on top and Black Iridium Polarized on the bottom - The peeling around the old lenses was pretty uniform, perfectly around the edges.