I had the DD Dualdisc of this and was disappointed with the sound quality. I now have the SACD and it's incredible. The sound is really good. From the low notes of the bass to the sometimes breathy or rasping trumpet/ sax. Even if you only listen in stereo, it's a worthwhile disc.
At first I was disappointed with the surround, even though I was well aware of the limitations. But now I have the SACD, I turned the rears up slightly and was stunned at the difference it made. (I don't think I have turned them up abnormally far - I often find I turn then up more (or down more) for other discs.) The stereo image is then wider than the speakers and there is some 'movement' towards the rears. I.e. though most things are locked in front certain pieces appear partially in the rears, too. I guess it's because the speakers are faithfully reproducing the sound being played back in a much larger room. That, in addition to the sound quality, makes it a very realistic experience. It feels like you are sitting in the studio watching them in front of you.
I know I'm not really saying anything that hasn't been said before, except I thought it was worth emphasising that this is worth buying for the surround, as long as you are not expecting some kind of early-Santana mix.