People make a bit too much of graphics. What makes VR different (and what will sell it) is presence.

Right now there are only some rules of thumb about what makes people feel presence in a game but it seems it doesn't really strongly correlate with graphical fidelity as much as it does with mimicking motion of the body with proper motion in the game.

This first round of VR headsets, in the hands of millions of people, will generate a lot of data about what exactly works and what doesn't in VR.

One benefit of the PSVR is that you already have at least one tracked VR controller that came with your PS4, and the old Move wands are back compatible. (I'm betting they unveil an updated Move when they release PSVR.)

Secondly Sony seems to be pushing a unique multiplayer experience so that two people can play the same game, one from the VR perspective and one from an entirely different 3rd person perspective on the TV.

Personally I don't think it matters what system you get this first round. They are all roughly equivalent. One thing you can say for sure is that they will all be outmoded, un-upgradable junk in under 5 years. And a future VR system will require another major outlay of cash on a HMD, not just a new GPU.

If say the 3rd generation of headsets are high frame rate, 8k or 16k displays with foveal rendering and GPUs tailored for VR, they will allow experiences that simply won't be possible on a conventional monitor because the identical GPU will unlikely be able to drive an equivalent 8k monitor at the same FPS as a foveal HMD.

So VR might reach the point of practical photorealism in games much quicker than people are expecting.