Hi
I have tried to sync with the SP-16 as slave both over USB (from multiple DAWs) and over MIDI DIN (from multiple hardware units, including an MX-1). In all cases, the sync starts to drift after a while, even when the SP-16 displays a solid BPM on the MIDI clock. This has the effect that the beat becomes increasingly out of sync over time. This makes it impossible to record a full, on-the-beat, arrangement from the SP-16 when it is set as a slave.
Note that the drift only happens when the SP-16 changes patterns, either by being in arrangement mode or by the user toggling patterns during playback. If I loop just one pattern it never drifts. This leads me to believe that each pattern change adds a short time shift that over time becomes quite noticeable.
I really hope that you plan to provide a bug fix release that addresses the MIDI issues that make the SP-16 so difficult to use in a production context. Other than that, it has been a solid product in my experience.
Thanks!