Being that there are so many faceless and characterless Beethoven sets on the CD market today, this set comes as a refreshing reminder of the days when interpreters were INVOLVED with the music they played! Yes, these are individualistic performances, but as in the case of Furtwaengler, this is the work of a thinker, a seeker who is not afraid of personal committment to the works he performs. And in fact, all of his tempo modifications seem to naturally arise from the ebb and flow of the music itself, rather than being imposed upon it. I find these Telefunken renditions much superior both in sound and in interpretation to the live Beethoven recordings on Music and Arts (formerly on Philips), which seemed unnatural and mannered in comparison to the smooth integration of tempi on the Pearl set. If you listen to this set at one sitting, I suggest you save the "Eroica" for the last, as this is one of the two or three greatest accounts of the score. By contrast, his older version with the NY Philharmonic on Biddulph sounds hopelessly stodgy, and the sound on that recording is wretchedly poor. The whole Pearl set is a real treasure, and here's hoping that the rest of Mengelberg's Telefunken recordings find their way to CD.