Today it's a so-so collection of unenhanced 78 dubs, virtually all of which are available elsewhere in comparable or better audio quality and with more informative notes and a more knowledgeable context.

That description is not at all accurate. The version of the anthology that was reissued in 1997 featured superbly remastered sound and notes that were so impressive that they were awarded a special Grammy. That package set the standard for all reissues that have followed.

If you want to an excellent entree into rural American music of the 1920s and '30s, and if you want to understand the music of revival performers like the New Lost City Ramblers, Dave Van Ronk, Bob Dylan and many others. The anthology is absolutely essential.