Really, twice each. Once ripped to WAV for Plex, a second ripped to lossless for iTunes.
I’m hedging my bets against Apple not letting me serve my collection locally any longer. ITunes continues to be iTunes. I can’t believe how slowly it all runs, aggravated by needing to use external storage—but it works.
With Plex, I have a migration path to an open source OS and commodity hardware. This is assuming Plex remains viable as a project, of course. But with WAV files I sould be able to convert to other formats with ease, and I hope that need won’t arise for years.