A few random thoughts - from someone who has been doing SACD for a couple of years.

For stereo listening I doubt very much that there is any audible difference between "normal" and "SACD" tracks - on the same disc.

For older recordings that has be re-released on SACD (like much of the Stone's catalogue), the audible difference between it and the older reelases is due to the remastering.

That same remastering into multi-channel is what has impressed me the most about the format. I believe that I can hear an audible improvement in the surround channels - but since I've never set up to do a proper comparison, it is perhaps attributable to wishful thinking on my part.

My bottom line is that I can spend hours and hours in my main theater listening to remastered multi-channel SACDs.