Incredibly comprehensive, covering all Jesus' parables, with plenty of insight and depth.
It deals with each parable in turn, from its wording and meaning, how it fits together, what may be original, what it may have been based on, to eventually its meaning.
It's this last area that misses the 5th star for me, as a preacher I could have done with some more thought to application. There are other commentaries for this of course.
I read about this on theologian Scot McKnight's blog and have not been disappointed.