Player piano authority Rex Lawson describes Dr. Edward Oswald Schaaf as an "intriguing musical figure of the early part of this century, whose compositions and arrangements occasionally turn up in American roll collections, but only very rarely find their way across the Atlantic to Europe. His musical style was somewhat florid, partly on account of his conception of the player piano as an instrument that could not easily bring out melodies without the doubling of voices or other contrapuntal assistance. Hitherto the player piano world has known very little about his life and work, which was surprisingly fertile, including nine operas, two masses, three string quartets, several symphonic works, and large quantities of music for military band."

Schaaf himself wrote "The player piano is rapidly adjusting itself to the highest artistic requirements, and is opening out a scope of hitherto undreamed magnitude to the imagination of the composer of piano music".

The Reliance Music Roll Co. of Auckland, New Zealand seems to have thought highly of his work. Several of his titles composed specially for the player piano were issued on the Reliance label.