I have the S900 with power switch on the front, and the Tyros3 and KX8 with rear mounted switches.

The PSR-S900's panel switch is far more convenient, but you get used to the rear mounted switches after several years.

Ian
_________________________
Yamaha Tyros4, Yamaha MS-60S Powered Monitors(2), Yamaha CS-01, Yamaha TQ-5, Yamaha PSR-S775.