Well,
I know the Mo8 as sampling and sequencing capabilities and the S90ES does not. S90ES can only playback stored sequences. I think the Mo8 weighes more.
They have the same keyboard so feel should be identical. Both are 1280 poly.
The Mo8 (not MoES8) has I think only 2 insert effects in performance mode, but S90ES has 8 insert effects. This would be important if you use performance mode.
Best wishes
Bob
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