Yamaha would do well to take as an example the Korg user guide that is perfectly clear and simple but especially trsdtaille approach.
Gnrale configuration and handling of extremely complex sounds and totally unusable without programming any prior notice for hours.


NOTICE GLOBAL

Using recent weeks.
I have also been a few months Korg PA500. Much simpler and intuitive especially with use in very quick evening.
I recommend especially not the PSR S900. A gale value, the Korg Pa588 is without doubt Superior.
Best Regards.