Looks very good mate. Good job.
Only thing I would comment on are the "dead" eyes. They seem to have no life to them, and being the first thing a person sees when looking at an image, it is a very important area.
This is a good resource for getting an approximate look, however it will take a lot of tweaking to get it looking "just right". http://www.andrew-whitehurst.net/eyeTut.html
It looks great man. Hope to see more!
Imagination is more important than knowledge.