Hi,
to create some materials exist one serious problem with the CoronaMtl - Anisotropy orientation (rotation). It locked to global (world) space and is a big limitation to create materials like brushed/satin metals, some fabrics (silk, satin, moire, taffeta, crushed velvet, etc...), brushed plastics/carbon fiber... Currently anisotropy in CoronaMtl is absolutely useless: in case of change the object orientation or complex curvature geometry - anisotropy orientation still in the same direction. I very much hope that in case of opportunity will be made Anisotropy rotation in object/local/UV space.
But also at this stage material is very good ;)