The value of this set is, in my opinion, many times the asking price. Although the track list at the top of this page claims 97 songs, this 10-CD set actually contains 198 tracks, which is practically sold for a song considering the hours of music you get. I found the sound quality to be more than adequate.
Although I was unable to correlate the album listing cited by the author of the September 23, 2007 review, some of the CDs in this set did match known albums. An example is disc 2, which is Cotton Club Stomp. Still, that review reflects a great deal of research and effort and is very helpful.
What I was able to determine is the tracks in this set span nine years from 1938 through the first part of 1947. That means that this set contains tracks that are historic, such as the ones with Jimmy Blanton who is the father of modern bass. In fact, this material is from a golden period in Ellington's life - one in which his writing was arguably the most prolific and his compositions were among his best.
Earlier I stated that the sound was more than adequate. My basis for that is I rip my music to MP3 files and transfer them to my phone, which serves also as my music player. That process loses some clarity of the music, yet the final product still sounds very good to my ears. If you are an audiophile you are probably not going to like the sound quality.
While I have many more Ellington albums and am fond of his 50s and 60s recordings, I find myself listening to this collection frequently. The music is pure American classic. Anyone who loves Ellington's music or is exploring his creative genius for the first time will probably find this set to be the value that I did.