I finally got around to installing the 2 TB drive I had sitting here for a while in my PS4. I'd already gone through the process once earlier this year, when I swapped out the stock 500 GB one for my old 1.5 TB. It's a relatively simple process, but it feels like it could be more streamlined. Backing up/restoring save files is definitely way more trouble than it needs to be.
This is as big as these drives come (at least right now), and once the long, long process of redownloading everything finishes it's going to be close to half full, just a year into the system's life. Sony's going to have to come up with something to extend it, ideally just letting me do what I do on Wii U and plug in an external drive.