This is an interesting time. I currently shoot H5X and Credo, and I have 4 lenses and no interest in investing in an entirely new lens system. However, both of these cameras are extremely interesting to me. Both get me higher ISO in a smaller form factor, and in theory, both may be able to take my lenses. The X1D having a Nikon hot shoe is very appealing, however, not being able to process those photos in C1 alongside my Credo and Nikon files is a dealbreaker for me. If I can process the Fuji files in C1 and use my HC lenses, and the price is as advertised, I'll probably pick one of those up and sell my D810 which I currently only have so that on commercial work I don't drop from 40 to 20 mp if I need to use my backups.
-Doug