Hmm interesting, thanks for that , I did not know they were still not really optimised like the textures are, 16 bit

I have also noticed that also by adding more noise it seems to help it, only thing is that its fine for rough surfaces like stone or render, however for smooth surfaces like metel or only slight render as in plaster walls and some slightly smooth concrete.

Another shadow effect that is terrible is the sawtooth pattern across some walls, how do I get it to be smooth?