The reason for that has nothing to do with the video source or the displays
good news,
The blurry edges is an optical effect, not all of us having the same distance between the center of our eyes,
makes the lenses at not the exact perfect position, from one person another, the other parameter is the shape and position of the nose,
which plays a great deal on the position of the device relatively to the eyes on the face ... that is the UP/DOWN and Left/Right very importantly too: How close will the lenses be to your eyes, this last point is the most relevant about this "imperfection" ...
Roughly, you have to play around a lot with it to find the perfect position, yes sometime you will feel some pain on the forehead and or nose
Push it much as possible toward the eyes, and we tend to forget the Vertical center, after having found the perfect width, you HAVE find the perfect horizonal position too
(up/down) +
the Angle ! it could be at the right height but with a certain angle, that is a party killer !
remember that each eye is a 2D optic sensor, like camera sensor, 2D means and X and a Y coordinate ... , the "3D" effect is handled by our brain that guesses/calculate the Y position of a point in space ...
(it's distance from us)
Sorry to ask but I have to: You do know that you can move the lenses horizontally ? just like the optician that needs to mesure the distance between your eyes ...