How do you feel about authenticity in recorded music?

Just heard an interesting discussion on NPR about Robert Johnson. There is some serious speculation that the recording sessions as mastered are much faster than intended, raising his voice and distorting the music. Another example given said that the early LPs of the Stones were mastered too quickly and that Keith Jones caught it when they were being converted to CDs. Would you rather hear the music the way you are used to hearing it or in the more authentic version? (With the Robert Johnson blues recordings there is no way to verify the truth.) Is there a place for both?