In the first few years of ministry I worked on building my commentary library by purchasing all the volumes in a couple of prominent series. After a while I realised what a mistake I had made. Sometimes the commentary would be helpful for preaching or teaching, other times the treatment was so sceptical it was useless. Even with the useful ones, I found that often I had purchased texts that were redundant. If I had it to do over again I would have invested more in researching my purchases.
D. A. Carson’s “New Testament Commentary Survey“, (6th edn., 2007, Baker Academic) an annotated list of all of the major New Testament commentaries, is an excellent guide to what’s available and useful. I recently purchased a copy as I’m rebuilding my commentary collection on the basis of more informed decisions.  I can see that it will pay for itself in both reading time and purchase price many times over.
I don’t imagine many people like me will sit down and read it straight through, but Carson’s writing is engaging enough to do so. This is quite an accomplishment for a bibliography.