I picked up the Centennial box at the end of last year. I don't think I would have stumped for 20 CDs' worth of downloads at about $8.55 per CD and only paid $200 for the set in shrink, so I'm still happy I have the physical box.
Will the eleven-disc Mosaic be part of this series? I have the three-disc tasting platter of that in The Real Duke Ellington, so I'd have to put some real thought into hoping for Mosaic to pop up for a price I could handle vs. just settling for the new download.
I hope the 1947-1952 Columbia material gets reissued in this series, as it has not been reissued legitimately in complete form, as far as I know. I only have one tantalizing volume as part of the five-disc CD that came out in Europe and would love to have it all.