I found a review on Amazon for Live and Let Die that contained the following snippet:
I would rank "Live and Let Die" in the second-tier of Bond novels, along with "From Russia, With Love" and "Moonraker." It doesn't quite reach the level of such absolute masterpieces as "Doctor No," "On Her Majesty's Secret Service," or "You Only Live Twice," but it's certainly superior to such relatively weak entries as "Goldfinger," "Casino Royale," and the disastrous "The Man with the Golden Gun." All in all, a classic Bond thriller.
I have to agree with A. E. Kaiser that Live and Let Die is a better book than Casino Royale. CR is not a bad book, by any measure I'm willing to apply. It's just that by the second novel, Fleming's already begun to get a much more three-dimensional brush stroke for his character and the world in which he maneuvers.
Seeing as how the next book in the sequence is Moonraker, which A. E. Kaiser puts into the second tier, I'm quite anxious to get started! And given that I can apparently identify the movie version of Doctor No in three notes, I'm not sure I want to wait for that 'absolute masterpiece' to roll around in the chronological sequence. But of the two intervening novels (Diamonds Are Forever and From Russia, With Love), the second is also in the second tier, so I'll struggle to hang on.