I must confess that I have not read Bonhoeffer widely, but this is a nice collection. The changing times that Bonhoeffer experienced certainly are visible in his writing, and the themes of hope and patience grow while the concept of coming judgment remains. If you are looking for warm theological fuzzies during the winter time, Bonhoeffer might adjust your outlook now and then.
The editor does a nice job of providing historical context for the reader, but he does seem to play a bit fast and loose at times with the content in relation to the title that he gives the book. Robertson also admits that he paraphrases in spots because of language differences and due to Bonhoeffer's penchant to summarize when speaking. I would prefer to read the man himself, but in the end, kudos to Robertson for putting an interesting compilation together.