bring your own computer and hook it up to it, see if you can get everything running
try out play, cue, loop, all eight feature pads on both sides
try all faders
try out the jog wheels
try master out for both XLR and RCA (might wanna bring adapters just in case)
try headphone cueing
if it’s important to your friend, try the phono and the mic
PS: Please be aware that this controller is only compatible with the macOS version of djay, not with iOS / iPadOS (see here) and that jog wheel displays, Color FX except filter, Beat FX will not work with djay
PPS: how do FX work with this unit if Beat FX are not supported?