The power in VRED is the ability to view something in realtime/VR then use the same data-set for a raytraced image. It'd be great if there was more control over how materials look between the two.
In the past I've created complex switch/variant layouts or even completely separate files between the two presentation methods... and I'm sure I'm not the only one.
The main issues revolve around transparency (including SSS) and displacement.
For example: Subsurface scattering makes a plastic material look odd in the realtime viewer - it'd be good if we had the option to toggle it off for the real-time view (or to choose a transparent/glass material to represent it instead).
An example for displacement would be that I don't want displacement shown at all in real-time (or a custom replacement Bump map is shown instead) due to the performance hit. I'd only like displacement active when I hit the Raytracing button.
Thanks.