I just want to endorse what other reviewers have said. This is an absolutely astonishing bargain. Three of the operas were recorded in Vienna, more than any other the city of Mozart, even if it didn't always appreciate him as it should have done in his life, with the Vienna Phil. and with the foremost stars of their time - della Casa, Christa Ludwig, Dermota, Erich Kunz, Cesare Siepi, Gueden, Danco, Corena, Walter Berry and others, with Krips, Bohm and Erich Kleiber directed, and the fourth - 'Die Zauberflote' - is a famous Berlin recording with Streich, Greindl, Haefliger, Maria Stader, Fischer-Dieskau and the wonderful Ferenc Fricsay conducting. There are some glorious voices and wonderful performances here, and it's nice to hear singers like Fischer-Dieskau and Berry, for example, fresh-voiced and early in their career. The recordings, from 1954 and 1955, are very good for their time, well balanced and faithful to the voices. In sum - very distinguished accounts in faithful sound, and for no more than pennies. I see no reason to hesitate!