Just tried playing it on the DK2 - latest Occulus Rift devkit. Was a cool, but very strange experience.
The scale of things in Quake is very weird when you're actually inside it.
And the position of the weapons. Because the Quake guy is a stumpy little dude, and the position of the weapons so, uh, strange, you basically have a gun for a dick.
The plasma dildo was especially misogynistic.
And by looking down you can see the muzzleflash model in your invisible stomach.
Still feel a bit queasy because of the speed of movement, but apparently that's normal until you get your VR legs.
It'd be great to have a proper mod using the Hydra's http://www.razerzone.com/gaming-controllers/razer-hydra-portal-2-bundle
I played one for HL2 where you had to gesture to use ironsights, throw grenades and reload.
Imagine axing a Shambler for 'real' - you'd probably end up breaking your hand on the desk.