It would seem to at least suggest that the corresponding hardware upgrade would increase data lanes to provide the faster throughput necessary to internally record 4K RAW. Otherwise, the hardware upgrade won’t be necessary. Depending on the cost for that upgrade, I may do it just to make the camera a little more desirable in a few years when I’m compelled to update. That said, it’s subjective as to what I’d be willing to spend. Maybe $500 if it included a sensor clean and any other minor bits?It would require camera hardware with a matching number of channels to take advantage of it. The Z bodies can support up to two channels. We don’t know if the PCI bus inside the cameras can drive data at 2GB/sec.