I have used Objective FCE in the past. It is published by Cambridge University Press and connected to Cambridge Exams who set the test. So it is very specific in teaching to the test. If you like that approach then it is ideal if not you may find it a little restricting.
In China it is absolutely necessary, in my opinion, to teach to the test with FCE because the question types and skill set required are completely different to Chinese high school English courses. You need to consider whether the same is true in your country when choosing a text book.
On the plus side it is colourful, has an interesting range of topics, is up to date with the latest revisions to the test and has a useful teacher �s book, work book, DVDs etc to accompany it. On the down side it assumes a level of general knowledge, awareness of western culture, ability to have and express opinions and life experience which few Chinese students, even in universities, actually have. More important from my point of view was the fact that it is one of the very few western FCE books allowed by the Chinese censors.
I have also used Objective PET which precedes the FCE book and Objective IELTS which follows it and they do make a logical progression for students who are in a long term programme.
On a slightly different note how many people in this site are teaching PET and FCE? I have some self created work sheets for these tests but I haven �t posted them yet because very few schools in China prepare students for these tests. However if there is demand in other countries then I am happy to share what I �ve got.