Realistic Digital portrait

Hello everyone! Here is a realistic digital portrait of a friend of mine, that I finished a while back. If I recall correctly, I may have finished it somewhere around the 5 hour mark. What I do remember, was how annoying drawing the hair was. I wanted to incorporate as much detail as I possibly could. It's not a perfect replica, but i'm happy with the results!

Here is the original:

Here are some of the individual layers:

Here is the final version: