There are big problems with the optics and resolution of the current rift display that would keep you from wanting to use it as a monitor. Even the HD version

There are big problems with the optics and resolution of the current rift display that would keep you from wanting to use it as a monitor. Even the HD version won't fix that, but perhaps the future 4K version will be better in that respect. Right now the pixels are too big, too blurry, and inconsistent with respect to turning your head or moving your eyes. All of these things will improve in time, but the current rift feels very far away from replacing a single 30" monitor at the job of displaying email or web pages (much less your enhanced virtual desktop).