The Yamaha PSRA3000 has the joystick which you can now assign to do all the things that the two assignable switches do on the PSRS970 and PSRS770. This new model caters to the middle eastern market with dedicated 1/4 tone scale buttons and arabic, turkish, Iranian styles but still has many of the styles from the 770 and 970 models. It also has the 512MB of flash memory to load in your own samples or yamaha voice and style packages.