This is a pretty good collective biography. It is, if anything, stronger about the relationships among the Impressionists than on the inner lives of the individuals. It's detailed, though not exceedingly deep--at the level of a good magazine article, say, only at book length. Upon looking at the endnotes, I saw without surprise that it's mainly based on material that's appeared in other secondary sources; there are no startling revelations culled from Monet's sensational secret diaries or anything of that sort. I didn't find the book "emotionally stirring," to quote a back-cover blurb quote, but tastes vary.
The illustrations are quite good, which is rather a sine qua non for a book about Art. They don't illustrate every painting described in the text, but they hit the high points, and of course they're very striking in their own right. It might not have hurt to have included a few examples of conventional "Salon" art, to demonstrate what the Impressionists were rebelling against. I was particularly struck by this:
|The Floor Scrapers, Gustave Caillebotte|
(hosted by Wikipedia)
I do think that a who's who right up front would have been a big help, particularly for readers who are perhaps less familiar with the Impressionist canon. If you're one of those, The Private Lives of the Impressionists will probably hold a good many "Wait, which one was Pissarro again?" moments. This is especially true once the various wives, sweethearts, mistresses, children, parents, and business associates come into the picture.
I might have liked Mad Enchantment more if I'd read this first, for background. More distantly, there's some crossover with David McCullough's The Greater Journey: Americans in Paris.