I think C 10 has worse performance than before.
Exact same buffer settings of 512.
Exact same arrangement. One Groove Agent 5 track and all other audio tracks with an instance of Scheps Omni Channel on each.
Results:
Cubase C 10.0.20: Best was maximum 37 tracks with clicks and pops. Tried all different settings.
Studio One 4.5: Best was 57 tracks.
Logic Pro 10.4.5: Best was 61 tracks. Performed perfectly until it hit overload and stopped.