I never got around to purchasing the 70-75 SACD/NTSC set; amazon.ca screwed me on it, and by the time they definitively told me that they could NOT get it for me, it was unavailable from other sources as well. So I had to borrow the set from a friend, and I can tell you that the audio quality is startling! There's a huge clarity, an authoritative presence, and strong bass in these new mixes. It was one of those SACD moments when I literally sat up, my jaw dropped, and I murmured, "Oh my god . . ."
Nick Davis, the guy who did the 5.1, said that the older albums (70-75) were obviously in poorer shape, sound quality-wise, and therefore show the most improvement. The latest albums were already sounding pretty good and so showed less apparent improvement. So when you do pick up and listen to the old albums on SACD . . . brace yourself!
cheers,
supervij