Quite fun, but lots of wishful thinking by the author.
I never thought I'd say this, but Rowling is way more realistic! True, she made lots of irrational mistakes, some of which are taken up in this fic (such as the purchasing power of a Galleon, stupidity of Quidditch rules, and rules of magic - Rowling just never bothered to make up a consistent set, the only thing she could do was to write "they took a lot of complicated notes on Transfiguration"). And people in Rowling's books do not act logically. But they are acting like people! And that's where this fic stumbles hugely, even more than in style of writing (I mean, in not having any).
The author of this book thinks that quite a lot of people are intelligent, and everyone who is not is a nonentity; he thinks that people want to be intelligent and make the very best effort to be intelligent all the time, not just sometimes. That's not true. People don't want to be intelligent, they want to be comfortable. Selfish in a way, but they are being people.
All the above is the more true for kids and teenagers. The best part of Rowling's talent is understanding children and recreating them faithfully. Clever or silly, obedient or obnoxious, trying to be grown-up even - they are all true to life. You won't find any of that here.
And, yeah, lots of people've already commented on this: this version of Harry is totally intellectually Mary Sue.