What. Eye tracking is the best thing about it. At least something interesting.
Shame about fresnel lenses
Well, we can be sure that Sony's engineers know better than us what the best possible trades are. And since reality is what matters, since reality is that all reviewers are finding PSVR2 image quality outstanding, that's what matters.
About that, one thing that is not appreciated about Fresnel lenses are God rays, but that has been almost completely resolved by Sony's Fresnel patent. Also, Fresnel lenses are significantly better than pancake in the amount of light that they allow to pass, allowing the use of OLED screens, traditionally less bright than LCDs. One more thing is that Fresnel lenses cause less pupil swim, which is one of the causes for motion sickness.
Those are things that in VR are significantly more important that avoiding a negligible amount of MURA in some dim situations (and that you notice only if you look for it, or if you are particularly sensible to it). Perfect lenses maybe don't exist, and the choice depends by what you want to realize and the overall cost. One sure thing is that the entire headset has been engineered in order to have the best possible experience at the cheaper cost possible, not to use various high tech components only to ruin everything using bad lenses.
They have a small sweet spot for the eyes, so to be able to see the whole image in focus, it's necessary to be sure to set everything correctly, but once it's done, the image is more than great. And luckily, the setup process is very simple and quick right thanks to eye tracking.