Name one aspect in which OVFs are more accurate. Many of them are not even exactly 100% of the sensor image, and they do not give any preview of what the actual image is going to be. EVFs give a pretty good perception of the image. They especially give you a good preview of the exposure. With the latest generation of EVFs, as this Sony camera has, their lag is actually lower than the one of an optical viewfinder. The OVF by itself has of course no lag, but when you press the shutter, the mirror has to swing away before you can take a picture. A mirrorless camera can instantly capture a picture, effectively having the smaller time differential between the VF and the picture taken.