I am a Toscanini fanatic, so I will keep it low-key and say only about his conducting that it is important for any classical music lover to know how he conducted the great classics, whether that person ultimately loves this or that particular interpretation. Toscanini's role in the history of conducting is objectively huge, and his interpretations had a huge impact on millions of people. For most people in the first half of the 20th century, including most conductors of that time, he was the greatest -- the Maestro of maestros.
This is an excellent value and the sound is generally very good, considering (a) the dates of the recordings; and (b) the not-so-good recording engineering that was used for Toscanini. It is a frugal set, without individual commentaries and without the libretti for the operas.
You will never never never hear an Otello, a Falstaff, a La Boheme, a La Traviata, a Verdi (or Cherubini) Requiem, a Beethoven Eroica (1939 and 1953 -- both different and both great), a Beethoven 7th (1936), a Beethoven 9th, a Schubert 9th (1942 and 1953, both different and both great), a Dvorak New World, a Pictures at an Exhibition, as you will find in this set!