I have 2 OTs. They sync perfectly. You can set one to mirror the other, so selecting tracks, cross fader movements etc etc on the master will effect the same parameters on the other, or you can simply use the master OTs transport to start and stop and work the 2 OTs faders and knobs independently. As mentioned in a different thread, with 2 OTs you can also automate one of the OT s fader movement via midi cc, which is nice.