The original Fleetwood Mac was in the top tier of the second wave of the British Blues Revival. Peter Green is a blues rock legend. The s/t debut and Then Play On along with 1971's Greatest Hits which compiles alot of thier singles which weren't included on thier studio albums are classics. With that being said, the Buckingham/Nicks era was special especially in the era of disco and punk. With Fleetwood Mac, Rumours and Tusk, I can't think off the top of my head of any rock band that released three consecutive albums of this quality in the last half of the'70's.