The XDJ-RR lets you choose how you'd like to perform.
You can plug in your USB drive and play tracks directly,
use Link Export mode to access your entire rekordbox
library via your laptop without needing to export your
music to a USB drive, or, if you'd prefer, you can connect
your PC/Mac with a single USB cable to harness
Performance mode in rekordbox dj. It's all up to you.