I rendered a few of my models and textures in C4 and I like it more and more.
Here is a machine of mine:
and another one:
And here is a test of one of my textures with different rendering modes:
normal-mapping:
parallax-mapping:
horizon-mapping:
Last one is impressive. It is better than parallax. It casts even shadows from materials on materials (self-shadowing) only from height map.
I will do some more experimenting with it. But up to now I am really impressed by the amount of lighting options, the optimized OpenGL shaders and the scene-management.
A quality demo with huge amount of details per zone should be possible there.