I got this in the mail today...
I wanted to make sure that these particular boxed sets had the same sculpts (it seems that each box is considered a "Part"); so the colors and sculpts are the same but just overlap in terms of the amount of each.
This is my 3rd box (of the same) and I can now say that they have the same contents Keshi wise; the only difference seems to be the tag team pairs (they might have 3 pairs in one color or one of each) & the Deka included in each box (2 per box).
No one box will give you a "full set" though, so by buying 3 of them I was able to complete some sets of colors etc
I am thinking these boxes are what sellers/dealers bought in the 1980's and just individually placed the Keshi in capsules/vending machines for sale in the respective stores etc
You can find these on yahoojapan, they pop up (I can think of at least 3 auctions currently).