I put off reading this book, because I heard a lot of mixed reviews. Mostly it seemed that people didn't like it when they expected it to be a continuation of the Harry Potter series. Therefore, going into this book, I tried not to think of it as a "Harry Potter book" per se, but rather something set in the same universe. Going into it this way, I think I enjoyed the book a lot more.
The real drawback to this book is that it is a play so that there is none of that beautiful, complex imagery and descriptions that helped make the rest of the series so great. The focus is on dialogue, which emphasizes how juvenile and corny some of the dialogue actually is. There were many moments where I had to stop and think, "Rowling would never write that." So it wasn't perfect. But what the book lacked in dialogue, it made up for in plot.
The story itself, which Rowling did write, is superb. I absolutely loved it. Is it as complex as the rest of the series? No. But it is still fascinating and beautiful and full of multiple layers of meaning. The interworkings of time and family and love and acceptance: absolutely amazing. In that sense, this did live up to the Harry Potter name.
As a play, there are a lot of awesome scenes and elements in this one, such as the staircase scene and the walking Sorting hat. Obviously you have to get a little more creative when making a play with magical elements in it and I think this was had very good strategies.
I think it really helped me to be in the right mindset before starting this book. I absolutely love Harry Potter and have been obsessed with the series for most of my life. I am glad that Rowling was able to give fans more stories from the Harry Potter universe, while still exploring a new format. I think it was a good compromise.