Well, it's full of Albrech Dürer's artwork, so of course it's great. The artwork is 5 stars, the text is 3, so I give it 4 as a whole.
It's also got a nice presentation of what was going on around him during his life. Dürer lived through an exceedingly turbulent time in Europe, as the previously unshakeable hold of the Catholic Church was shattered by Martin Luther and the Protestant Reformation. In addition to all of the other ways in which this was important, this had a profound affect on the primary sponsor of art in Europe at that time, and Dürer was one of the generation of artists who had to find a different way to make a living than relying on the patronage of the church. Perhaps partly as a result, Dürer's paintings and woodcuts reflect a wider variety of topics than it might have if he had been born a century before.
The text that accompanies scores of Dürer's works, and roughly as many works by his peers and forebears, is not bad. The author does have a curious grudge against Dürer's wife, going out of his way on numerous occasions to describe her in a negative tone. As far as I can tell, there isn't much source for this other than the fact that Dürer wrote a letter to one of his friends in which he was not happy about her, and one of his friends didn't like her, but for all we know this was written during a bad week in a good marriage. He used her as a model several times throughout his life, and went on a year-long trip with her when he was in his early 50's, so they must not have been all that upset with one another. I think it is a common failing of historians or writers whose subject is centuries in the grave, to believe themselves better informed about the subject's personal life than they are. But regardless, if one ignores that, the text does a good job of telling us things like, who was Dürer making this for? What previous works was it similar to (or a marked contrast to)? What would the intended audience have seen in it that we in later centuries normally miss?
Really, though, let's be honest: you don't get a book like this for the text. This is Dürer's work, and lots of it. The man was nearly unrivalled in his own time (Hieronymous Bosch, in my opinion, was his only true peer), and still stands out five centuries later.