This is a review on the 4th edition. Being Brazilian myself, I bought this book as a gift for a British friend who has a Brazilian partner, but I decided to examine it beforehand. I have found things that strike me as simply unacceptable in a phrase book.
The translator, or whoever was in charge of the text, often makes mistakes that suggest she/he is not a native speaker, or that she/he has been living abroad for too long. Some examples: "portuguêses" (wrong accentuation), "pasagem" (wrong spelling), "amanha" (missing accent), pronunciation of "você" misleadingly indicating that the first syllable should be stressed, "kilo" (wrong spelling) etc. - all that was just in the first pages. The translator also seems to have a problem with the crasis accent, which appears to be wrong almost every time.
If you follow the book, you will end up saying "É um hora" (It's one o'clock) instead of "É uma hora"; if you are vegan, you will use a word just invented by this book, "vegitalista" (there is no such thing); and the crying-out-loud, ear-hurting error that would be unacceptable even at a kindergarten level: "estrupo" instead of "estupro".
The very low price and the huge variety of situational expressions included in the book may compensate for the errors for some people. (There is even a very amusing section on sex talk!) However, on almost any given page I randomly pick, there is a typo and/or a grammar error. I have learned that most typos are actually consistent spelling errors. In addition, errors in the pronunciation keys are not rare, sometimes indicating the wrong syllable to be stressed. That brings us to another serious problem posed by the book, which is the pronunciation system (barely understandable) and the choice of a regional accent. Do not believe them when they say that there are small variations in pronunciation across the country. I am not saying that they should provide a key for all possible variations you can find, but the differences can be huge indeed, and this book does not even mention that.
To sum up, it should have undergone serious proofreading before being published. The way it is presented now, it damages Lonely Planet's reputation.