Oh, this book. I have a lot of conflicting opinions about it, and it all depends on which chapter we are discussing. It's sad, but the quality of the writing differed greatly between individual chapters.
Overall though, I would say that this book by Marek has a misleading subtitle. I don't see this subtitle in this English version, but the Dutch subtitle is "The ruination of the Habsburg House". Considering the book ends with Franz Joseph's death, which happened before Habsburg fully collapsed, that's a wrongly chosen title.
The English subtitle, "Franz Joseph, Elisabeth and Their Austria" is more fitting. This book is a mix between a biography on Franz Joseph, and trying to explain the events that led up to the First World War. As a biography, it fails: Marek is subjective, and seems overly biased against Franz Joseph (I understand his reasonings, but as a scholar you should at least *try* to be objective). He seems to feel more sympathy for Elisabeth than she deserves in this context (surely she was pitiable in many ways, but her political actions leave a lot to be desired). Rudolf and Franz Ferdinand really get the short end of the stick, Franz Ferdinand hardly has any good character traits, judging by this book. Rudolf's only memorable mention in this book is the summary of the events of Mayerling. Marek makes the comment that Franz Ferdinand's politics would likely have ruined Europe, but Rudolf's ideas aren't even mentioned, like they were of no importance at all. These are just a few examples, but I think it shows Marek's weakness as a biographer, and that he talks selectively about what happened.
It's not to say that Marek's book is entirely subjective or untrustworthy. It's clear that he has done a lot of research, and one thing I really appreciated were the transcripts of conversations he included from time to time (many of which I hadn't read before), and his description of Viennese gossip. He doubted many of these stories, and gave own interpretations, but in this case that was fun and enlightening: as it was clear he was offering his own opinions (also mentioning the reasons for his conclusion), and the gossip was generally just fascinating to read about.
Throughout the book, Marek seemed to have structuring problems: in the first few chapters, for example, he'd start off with the 1848 revolution, then include a chapter on Franz Joseph's life from birth till then, and then pick up his revolution story again. The structure was therefore slightly confusing at times. But the moments where he structured properly (most notably, the last half of the book) were clear, and concise. It's a shame not the whole book was written like this. His chapter on Mayerling is probably the clearest I have read on the topic (and I have read quite a lot about this), and the way he described Sisi's murder and the build-up to the Serbia conflict were good reads.
The thing that frustrated me most, is that he ended with Franz Joseph's death. The book had also attempted to describe Vienna life, and the lives of other prominent figures, and the political situations in Hungary and Serbia (other countries belonging to the empire were generally only mentioned in passing), but in the end Marek doesn't talk about the end of the Habsburg House, or how the war played out. He just gives a few statistics, and that was the end of it, for him. I suppose that's the signal for me, to pick up another book on WWI Vienna.
Shortly said: the combination of political history and biography doesn't always work out well, so if you're especially interested in either the politics or Franz Joseph and Elisabeth, you might want to pick up another book. I wouldn't recommend this as an introduction to the topic of Franz Joseph, Sisi and their Austria. But if you know a bit more, and know how to navigate around fact and opinion, Marek does offer some interesting insights, opinions and details.