How accurate is "Empress Dowager Cixi: The Concubine Who Launched Modern China" by Jung Chang?

I heard her give a (completely preposterous) interview on NPR that made me question her credibility, and I posted a question here as well. I got linked to this review by a flaired user that is similarly unkind.

All complaining aside, I only got this off the library new books shelf because I thought there might be some eunuchs in it, and there were, so not too bad on what I was looking for. But this book was a sort of epic revisionist dick-riding of Cixi, which I was not totally expecting, nor did I think anyone would ever write. Cixi gets a rough ride in traditional historiography of China, and I’m sure she wasn’t as totally evil as she gets made out to be, but she also wasn’t a dang national hero like Chang seems to want her to be. There is for sure a very interesting story to be told about her life, but it is not in this book. If you would like to watch an author casually handwave away murdering family members as not a big deal and totally reasonable in circumstances, plus some really clumsy writing, you might get a kick out of this book. But otherwise pee pee doo doo, this is a bad book, don’t read it.

Seems like she's a novelist who's taken to writing nonfiction because she has an axe to grind, not because she has done any novel research on her subjects. I think even if you accept that traditional historiography is biased heavily against Cixi, and her gender is definitely a part of that, it's very hard to square documented facts with a totally revisionist, entirely positive portrayal of her actions.