"Better than prior reviews led me to believe"
I'm not quite sure what the others are talking about.
The reader was adequate. He certainly wasn't superbly engaging, but neither was he so horrible as to make the book unlistenable.
I was quite able to at least get the idea after a single listening, and so I don't think this is a bad format for less strenuous digestion of "Structure." Indeed, if you listen to it many times it might serve to totally replace the book.
Perhaps it is right to say that academic books usually reward slow readings and re-readings while stopping occasionally to consider what's being said or what has been said. The pause and reverse buttons can facilitate some of this with an audio book, but obviously this type of digestion of a work is more suited to reading than to listening. However, for a first time read-through this audio book will more than serve.