Speaking on the VR thing, I start with the Google VR apps on Android smartphone.
I do not own a Google cardboard, but owned a VR Box, China made plastic phone VR headset that is compatible with smartphone that is up to 5.7" screen size, with adjustable focus, and eye distance, together with head strap.
This VR headset just cost me around RM50.

The phone that I test is OPPO Find 7, with 2K screen, 534ppi, and Xiaomi Redmi Note 2, with 1080p screen 401ppi.
Simply, the RN2 screen is pixelated on the VR, then the Find 7 screen is near perfect, almost no pixelate visible (may still notice if look carefully, but already miles better, not much obvious)
I try the sample 360 video file from Youtube, but Youtube video file simply is very low quality, I can see a lot of compression artifact, but for real high quality 360 sample video download from some website, it is simply awesome.

Then today, I go to the Samsung road show to try the Samsung Gear VR with the newly launched Galaxy S7 Edge, 2K screen, 5.5", 534ppi.
But sadly, it's AMOLED screen with pentile pixel arrangement kills the VR experience, simply I can see individual pixel of the AMOLED of diamond arrangement.
The demo staff try to argue with me where he claim the 360 video played in the headset is not high quality enough, but the reality is, the pentile AMOLED screen simply is not high fidelity enough, visible too much hollow between pixel, and can see individual sub-pixel color.

So, I can safely say, the screen on LG G3, LG G4, LG G5, Sony Xperia Z5 premium, Meizu MX4 Pro, ZTE Axon Pro/Elite, simply are much higher fidelity than the Samsung smartphone AMOLED display when come to VR.
This is because LCD screen employ full RGB color for each pixel, and the gap between LCD pixel are much narrower too, simply easily trick our eye to forget the screen we see is still made up of visible pixel.
Sony Xperia Z5 premium with 4K resolution, got insane 806ppi, is the king of VR for smartphone. Hope Sony can launch their own VR headset for the Xperia Z5 Premium.

I already disappoint with Samsung Gear VR. Maybe they will release a 4K AMOLED smartphone to solve this issue.
I hope that this Sony Playstation VR screen will be much higher fidelity as well, simply fit in the 4K screen in the VR set, and launch game that can run natively in 4K resolution, provided the PS4 can render the game in full 60fps in 4K will be much appreciated.

I read back the comment, seems the VR will have very less market share, and may fail like the 3D TV, 3D game case.
It is not related to slow user adoption rate, but rather, the virtual reality stuff viewed on our eye, generated by the headset screen, is not very comfortable to our eye.
The point like cannot use it for long hour is very correct and true, it will hurt our eye in long time usage.

My experience with the smartphone VR is, I only can wear them for a few minute.
The longer I use, the more headache and eye strain I feel, simply feel dizzy and want to faint.
The feeling is much worse than wearing 3D glass for 3D movie watching.

The glass free 3D, seen on Nintendo 3DS, and HTC Evo 3D smartphone, also is distracting to my eye after long watching., I simply turn off the 3D effect to stop eye fatigue.

So, 3D, virtual reality stuff still need much more work on the refinement before really able to work comfortably.
Or, they may not even have any bright future, as they post health issue on the usage.