Cannot comment about C1, but there was a time that many people saw problems with the way LR handled the X-trans files of the Fuji APS-C cameras. Some went to C1, others to Iridient, many were perfectly happy with LR. I believe the GFX cameras are Bayer array sensors and LR should handle the files as well as it handles any other Bayer array camera. When I rented a GFX, I used LR and otained what I thought were spectacularly lovely files.