Seeing Blokeman's post above inspired me to add this.
I have exposed MGIV in-camera. It reproducded blue objects at one contrast, and green objects at another contrast. It also centered my MacBeth chart neutral scale when I used ISO 25 on my meter indicating an ISO speed of 25. Of course this is only approximate due to the high contrast of a print material (~2.5) vs a negative film (~0.6). Therefore a graded paper of about 1.0 would be better than a 'normal' grade.
I used a 4x5 sheet of MGIV exposed in my speed graphic. I believe that I posted a scan of that in another thread.