That's an interesting read, Flagbit. It's also further proof that a good microSD card can easily match or even beat a USB-connected mechanical hard drive, especially on small file reads/writes where even the best spinners often struggle to exceed a miserable 1MB/s. Overclock the card slot as well if it's a UHS-rated card and you can be miles ahead on typical spinner I/O performance.
Pi2B Mini-PC/Media Centre: ARM=1GHz (+3), Core=500MHz, v3d=500MHz, h264=333MHz, RAM=DDR2-1200 (+6/+4/+4+schmoo). Sandisk Ultra HC-I 32GB microSD card on '50=100' OCed slot (42MB/s read) running Raspbian/KODI16, Seagate 3.5" 1.5TB HDD mass storage.