Hello,
I ve a good experience in working with Houdini and Redshift as render engine. Recently I tried to use Arnold because in th project Im currently working on I needed to develop some NPR shaders and Redshift was not really the best for this job. However I noticed immediately that when I update geometry at sop level, transforms or other things, the render did not update automatically. Do you know if there is something that can be done or it is a missing feature? Also if you have some suggestions about working in Houdini with NPR you are welcome.