Looking at each one of the work components (modeling, detailing, texturing), its definetely great high quality work.
The way things are working together in the images you posted don’t seem to bring justice to all that work. Maybe its the lighting, too much light. For instance, the arm pit region seems less occludded than it should.
The BW image doesn’t seem so affected by this but it still display some sort of glow in the occludded areas, for instance the inner elbow region.
The facial expression seems to be exactly the same in both poses. It works fine in the stand up one, but sitting it doesn’t seem very natural.
I’m pointing these details ( which may be of subjective nature) but I’ll say it again, its already an amazing and impressive work.
A level I’m hoping to achieve soon.