One of the most important tools for a tango DJ is a well organized library of tangos. The dancers have no idea how much time we spend organizing, tagging songs with recording dates and trying to find the best quality versions of the songs available. We constantly have to work on playlists of an orchestras or a singers dischography in chronological order, to find out which songs are still missing, and also to get a more clear perspective to the timeframes in which each song was recorded. Having a clear list of the recordings in order, will allow us to evaluate the progression of the orchestra and their selection of songs more thoroughly.
I also know that some recordings from Enrique Campos with Ricardo Tanturi are missing from the list of www.tango.info like the milonga "Quién canta mejor que yo" (YouTube)
However, all these songs are available in the TangoTunes online store. Also notice that most of the songs on Spotify are in bad quality. When you want to purchase the songs I highly recommend getting the Tanturi's from the TangoTunes store