My son, age 9, says - "It was a very good story but the end was very sudden."
I say - "It was a good story and my son and I play Minecraft alot. I didn't know who Herobrine was when I started the story. The characters were good, especially their relationships. I was a little surprised at the abruptness of the ending, but i now know there's a sequel.
My only complaint is that it is badly punctuated and there are numerous errors such as made instead of make. I am glad I read most of it to my son.
At the end of the day my son enjoyed it, and wanted to make Herobrine's house on our PS3, so I suppose you can't say fairer than that.