I remember this was the very first Disney Fairies book that I read. It was a while ago so I don't remember the details except that I enjoyed it. It's even more interesting for owners of tinker fairies to read, you get to immerse into their work a little bit.
I agree, Fairy Tag sounded very interesting! When the game was still open, we could fantasise about what new features could be released and the books had heaps of ideas for it. Fairy Tag was definitely one of those ideas that we would have liked to see in the game.
I didn't know there were different authors writing these books, you can't even tell the difference if you don't know about it in advance.