I don't believe that I've ever encountered
any book with as pronounced a contrast in pacing, between its first and second halves; it was quite literally like a different author had picked up the story midway.
Most days, about the only free time that I have for leisure reading is after I've gone to bed, and, with GoB's first half, it was all I could do to struggle through a few pages - at most a chapter - before I was bored and called it a night. I even took a break from it completely, at one point, and read another book (A Breed Apart, by Pierre Davis - excellent!). It ended up taking me nearly a month to get to the halfway mark, and if it hadn't been a soon-to-be Bond novelist's work, I might well have just ditched it, in the end.
Really glad I didn't.
A bit more than halfway through, as Paul is preparing to finally do the deed, this book suddenly becomes electric. I found myself staying up till 1 a.m., reading "just one more chapter", and then another, and I think I read the last half in just three days.
My concerns about certain plot elements are minor, and are pretty much the same ones mentioned by previous posters - in particular,
One side-effect of having read this book is that I'm now interested in doing some non-fiction reading about Hitler and his cronies - their rise to power, etc. Quite honestly, the Second World War has never interested me all that much, but reading GoB has made me want to know more.