PSR-S670 was a rather successful keyboard; for a reasonable price it sounded like a professional instrument and had a lot of controls. I see that Yamaha targets specific products of its rivals, in this case it was Korg PA300. Yet, it doesn’t want to sabotage its own TOTL products, so S670 was not very convenient without buttons on both sides of the screen. It would be up-to-date to put a touchscreen on SX600, but without new competitors from Korg or Casio there is not pressure to do so. Yet, there’s Medeli, but how serious can it be, given that it uses Yamaha’s sounds?