I've actually used Daydreams VR, Gear VR, and the Vive.
I have not been impressed though. It always just feels like a 360 degree computer monitor. Hell, the phone VR systems are just terrible in general with abysmal resolutions.
I gave up using the Playstation VR thing at a friend's place for Resident Evil because the discrepancy between the controls, on screen action, and what I was actually doing was too jarring for me. Not to mention the graphics were noticeably worse in VR than normal. To give an idea, to see "yourself" move "your" hands around while your real hands are just on a controller feels really disjointed. Every time that happened (basically nonstop) I kept losing my immersion. Also it had to keep fading to black whenever "your" head moved too drastically from what your real head would be doing. Basically, every single time you crouched, climbed a ladder, sat down, got thrown back, etc. etc. Again, very weird and disjointing.
I'll also mention VR porn, which I've also tried. Extensively. I do not really recommend it for the same reasons. I've read about people going "holy shit VR porn will make the human race go extinct" or whatever but it really isn't particularly great. Again, you have the same problems with what's going on on the screen being completely different from what you yourself are... ahem... doing. They can't move the location of the camera for fear of motion sickness and it just being really strange if they did so everything happens from one single camera angle. It feels alien and weird, like you've been transplanted into the eyes of someone you can't control. You want to move but you can't. All you can do is move your head like some sort of coma patient being molested. That being said, I'm sure if you're someone who does not have a lot of experience with tits hanging in front of your face, you'd probably love this as it feels quite real in that aspect.
I doubt I'd be running out to buy a Vive to play frigging Fallout 4 in VR.
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As on now, the only time I've preferred using VR over a regular screen was during racing sims. Then it's frigging amazing. I was completely and totally immersed to the point where I felt like I was racing a real car, checking my mirrors, looking at my car dash and so on. If you're a hardcore racing gamer, I highly recommend VR. I would imagine stuff like Elite Dangerous would be amazing with it too, but I haven't had a chance to try that either.
FPS... not so much. Maybe when they implement some kind of full body harness / controller. Because right now you can't even bloody crouch without it fading to black.