I recently received Slave, by John MacArthur, from Thomas Nelson for review purposes, and began reading immediately. It's very well-written and clear. It's deep, helpful , and profound. The main point of the book--that we belong to Jesus, not ourselves--is sadly missing from most teachings these days.
Having said that, there are a couple of things that keep me from recommending it wholeheartedly:
1. The gist of the book's message is spelled out nicely in the first two chapters. Everything that follows simply expands on the contents of the beginning. Like a Saturday Night Live skit that was great at 5 minutes, but unfunny when made into a 90-minute movie, Slave stretches a great teaching a bit too thin.
2. The "slave" language is very uncomfortable to me. The author backs up each assertion very well, so I know it's all accurate, but still, the idea of slavery seems like a terrible thing, and I have a hard time getting past that. I'm guessing I'm not the only one. And I am a white guy. I can imagine how an African-American might be even more sensitive to the main point of the book.
If you can get past those two items, though, it's a good book with the right focus.