NEVER get lawyers involved! All that is required is that the monitors meet DICOM part 14 GSDF standard. DICOM preset is an OSD option for all 90 series and PA_01 series including the 3090 (although NEC doesn't include it in its list of DICOM conformers...
I am currently deciding btwn the two 30" NEC displays. I am aware that the 3090 is end of life and offers little saving off the new PA 301, but I don't need the colour gamut, and in some reviews the older model achieved better black contrast. Plus, this will be used for medical applications and...