Those who need a USB 3.0 hub with just two ports and a large hard drive can get away with the Seagate Backup Plus Hub, which is usually cheaper than the sum of its parts. In my case, the Backup Plus Hub comes with a Barracuda hard drive inside (8 TB, 5400 RPM, 256 MB buffer), but for ~15% less than the drive alone.
https://www.notebookcheck.net/Seagate-Backup-Plus-Hub-8-TB-hands-on-An-USB-3-0-Hub-and-a-5400-RPM-Barracuda-combined-with-decent-results.520010.0.html