Dave,

As long as your mirror rig has the cameras properly oriented and both sensors scan from top to bottom (or vice versa) rolling shutter 3D problem is essentially eliminated. Output image flip is simply for operation, rig alignment and other practical uses. Not to speak out of school, but from knowing many (very busy, very conscientious ) REDheads I would say that these features have not yet been implemented because they have other more highly prioritized things to do first. Not everyone with EPIC is shooting 3D. I know, crazy right?