However, the majority of VR-ready PCs will be able to run smoothly, with only occasional lags and framerate drops. PS VR, on the other hand, is guaranteed to work with any PS4 out of the box - although the PS4 Pro promises more powerful performance.
In terms of display quality, while PlayStation VR is nominally lower-resolution than the other two headsets, in practise the difference is all but imperceptible. Part of this is the fact that most VR games are designed to be low-res, cartoony or retro experiences, but a larger reason is that the experience is generally so immersive that you simply don't notice minor anti-aliasing or artifacting issues.