TL;DR down at the end of the post.
Medium/Long answer: Fan boys will say the Rift S is objectively miles better just because of the fact that it has subpixels. Subpixels basically makes the color production more smooth, but it will not make the image sharper. So the take is: The Quest has a sharper and more clear image, while the Rift S has an overall smooth image. Side by side you won’t really be able to tell the difference.
Also take into account that while the Quest do work as a PCVR headset, it still has some latency issues and won’t currently work as good as a tethered experience (like the Rift S). Oculus is working on solving this issue, and if they do then it’s over and out for the Rift, sadly. They might already have, but they are a smart company and need to continue to sell every device from their product line until they see fit.
I chose the Quest mainly because of it’s ease of use and the insane amount of love and updates it’s getting. You can bring it with you wherever in the world and it’s super-easy to set up. The visual experience can be compared to a Vive Pro (used to own that headset). You sacrifice some graphical fidelity, but not enough to really care or notice while in the metaverse.
If you want portability, no wires, and a great VR experience: Get the Oculus Quest.
If you want to play PCVR games and don’t care about the latter: Get the Oculus Quest. (:D) ...or wait for HP Reverb G2 reviews!