Controller

DDJ-RZ is a rekordbox dj controller

DDJ-SZ is a Serato DJ controller

Ma a livello di hardware e funzionalità?

E inoltre, e meglio serato o rekordbox?

For the most part the units are similar.  The RZ has some rekordbox-specific hardware buttons such as the sequencer section, release FX, etc.

It's really all a matter of personal preference.  Rekordbox dj is growing quickly and adding new features and supporting more and more equipment.