Rubio, The set has had more or less universal praise. Part of its value lies with the notes that Graham Johnson wrote when he devised each disc. However, I have a feeling that the box-set has words, but not the mini essays to each song. Nevertheless, it is a great set to get hold of, especially if you can obtain it for a good price.
Most of the discs are designed around specific singers and contain a mixture of famous and obscure songs.
Schubert's duets and part songs are also in there, it really is very complete.
Mike