OP11 discontinued the integration of VP, and I don't know whether the newer PhotoLab has re-integrated it or not, or whether the distortion correction is available in PL independent of VP. I can also set the aspect ratio to "unconstrained" to get the widest possible FOV (much longer in one dimension). Rectilinear distortion is almost completely gone and progressive edge sharpening further improves the result. I use VP2 integrated in OpticsPro 10 Raw processing. I don't have a MF camera (yet), but Viewpoint works easily and brilliantly with other camera formats' FE captures. I have DxO Viewpoint 2 and VP3, which are very useful for perspective as well as FE correction. The sample below was shot on mFT with a Rokinon 7.5mm FE lens. The only thing to be concerned about is possible lack of support for new cameras and lenses, but manual corrections are always an alternative (and may be better, anyway). I don't see how DxO's bankruptcy interruption should affect one's decision to buy and use it, since your manual defishing will be available indefinitely (as long as your OS supports it).
You can download free trial software and see for yourself.