What's the difference between the ddj sz and the ddj sz2?

The grid adjusting buttons have been swapped out for Key adjust/sync buttons (for Pitch ‘n Time DJ).

Two new buttons have been added for Serato Flip control (record and play) above the loop section on each deck.

The performance pads have a new shift layer for turning on Pitch Play mode.

Improved jog wheel latency.
“Cymbal” and “Horn” oscillator sounds are replaced with “Drop” and “Siren”
Each deck has a quantize button below the jogwheel – allowing DJs to quickly turn on and off the setting (as on CDJs)