One book, at least for me, never feels like enough. :/
I have the Excel, Macquarie, Macmillan and Heinemann.
I've also used Cambridge before, but only briefly.
Excel is good as a reference. It's fairly thorough, though I don't use it as often as I did for the preliminary course (with reference to preliminary book, obviously).
Macquarie is good as a summary, but it can be exactly that. Too summarised. It's got a good number of cases in it, though I often find myself having to look them up because they're given too briefly.
I couldn't give a good comparison to the Macmillan and Heinemann - they're both similar in format and textbook-like. Both have different cases though and may cover some bits of topics better than the other. Though I can say if you like mind maps (as my teacher does), you'll love the Heinemann book.