As far as how the CD layer sounds - some songs are better than the old London CDs, some are about the same, and some are a tad worse. I've got a review of the sampler CD here:
http://lukpac.org/stereostones/review.html
Another note, not in the review (yet) - Honky Tonk Women is slightly...
Keep in mind the Stones discs are NOT being marketed as SACD discs - that's kind of a "hidden" bonus.
I've got some comments about the sampler disc on my website:
http://lukpac.org/stereostones/review.html
http://lukpac.org/stereostones/