PCMark and Windows File Transfer
PCMark's data drive benchmark examines NAS products through three traces that entail copying 339 JPEG files to the server (write test), making a copy of said files (read-write test) and then copying the files to another drive (read test). The DS220+ struggles in this particular test when compared to its quad-core, four-bay sibling, the DS920+.
Copying files and folders to and fro the NAS from a Windows 10 client paints a picture of real-world everyday performance. The results confirm that the under-the-hood upgrades are incremental and the Gigabit Ethernet interface is a bottleneck.