If you want to read a book about time travel, choose this one instead of The Time Traveler's Wife. The story was enjoyable, the characters interesting. That said, I kind of thought the book needed a bit more editing. The main character's life needed more filling out, and some of the relationships were just a little unbelievable. I wanted more on the main character because he was written like a superhero. He's great at everything, not just an athlete, but capable of writing philosophy... does he have a flaw? This gets fairly nauseating over time. 
 I found the (brief and light) discussion of Vienna at the turn of the century, the major players and the political antisemitism very interesting. Note that the author worked on this book for over 30 years. I think I expected a little better. Still, a good summer read.