Tony, I do the same thing, since outdoors I use the EVF almost all of the time. Since you can view the image, after taking the shot by pressing the view button. I would rather change batteries rather than to pay for replacement of an on/off switch.I also worry about life of the on/off switch. I prefer to leave the camera on. One thing I sometimes do is switch off the eye detection on the evf. Stops the camera “waking up” if you dangle it near your body. I do this especially when using the “pancake” 14-42 lens with its motorised parking, as constant retracting and extending the lens must add wear and use loads of battery.