37mm lens for Mamiya RZ, has anyone experience with

Hi
I would like to use/hire a 37mm lens for Mamiya RZ in the near future and
would appreciate any feedback from anyone who has used it.

I am interested to know if there is significant image degradation at the
ends of the aperture range ie wide open or at F32?

The lens allows the use of the 40.5mm filter on the rear element of the
lens. Are there any problems when using these filters? Can more than 1
filter be used eg an ND and a Colour balancing filter or would these
protrude into the path of the mirror? I would imagine that a polariser could
not be used but does anyone know for sure.

What is the image (sharpness/contrast) from the 37mm like compared to other
RZ lens'. For comparison purposes, I have the 50, 110 and 210Apo. I find the
50 is good as long as you don't use it at F22 or wide open while the other
lens are generally better throughout. In my applications I would generally
use a lens at the F16-F32 range and probably never wide open.

Thanks in advance.

Regards
JJ