Correction
The capacities are 375GB, 250GB, and 64GB. The middle one is not 350GB!
WDLabs has introduced a Raspberry Pi storage subsystem with three drive products and multiple OS project spaces. The Brit-designed, credit card-sized computer is hot stuff – some ten million have been sold since the first generation's release in 2012. WD's PiDrive Foundation Edition products combine microSD card and USB drive …
The Pi is a nice piece of kit until you try to use the USB in earnest. As in storage, uvcvideo or god forbid a combination of them and or networking (which is also off USB).
I tried building a "DIY Time capsules", "outbuilding servers" and/or CTTV systems out of one of my spare Pis. The moment I tried attaching a decent drive to them they no longer survived receiving the weekly backup (situation was OK with older slow drives). Ditto for running USB 3G modems. Ditto for trying to run the wifi as an AP (as it is over the same broken USB). Ditto for trying to run any serious storage/network load while having a USB uvcvideo. And so on.
If you really want storage on an Arm Soc - get a Banana. I have not had a single issue once I replaced my "USB in use" Raspberries with tropical fruit and relegated the Razzies to duties which do not involve strenuous USB exertions. When you do not need to use the USB, the Pi shines by the way - I have systems with 6+ months uptime doing motion using the built in camera and/or stuff via GPIO.