Well, I admit that I don't get the 'Cube map' projection (+x, -x, +y, -y...) to work at all properly - not to mention with stereo output.
Up to now, I render first the left, than the right image (spherical [=equirectangular] projection, in Archicad) @ 8.000x4.000 pixels.
When Paul will make it possible to us to render with e.g. 30.000 pixels wide, so with stereo 'side-by side' and spherical projections, you'll get
an effective stereo image with 15.000x7.500 pixels in one render job.
By the way, here an example of mine; effective (stereo) resolution is 8.000x4.000, works fine with my google-cardboard-like device (2.048 x 1.536 screen),
just activate the VR-glasses-icon at the bottom:
http://planung-visualisierung.info/00.P ... 0frei.htmlArtur