Right, well I have a real history with this box set.
The first appearance of this music was two separate Sony LPs that came out in Japan. I heard about them, but never found copies at their release to buy. Then Columbia US put out the two LPs as a two LP set and that became almost my favorite Miles for a while.
About ten years later I'm in Austin, TX and my best friend, trumpeter Dave Laczko, is the jazz and classical buyer for Tower Records. He hears that Japan is releasing a 7 cd set of Plugged Nickel and that only about 200 are going to be sent to the US for Tower stores. He wrangles to get 2 sets for Austin, one for him, one for me. But. . .they never came. Apparently Tower NYC managed to keep most of them and jilt the other stores. We fussed and fumed, huffed and puffed, and never could get any of those sets.
Finally years later Columbia US released the set you have (and I have) without the edits that Teo Macero did for the Japanese set. I was very happy to have it, loved it, listened to it a lot. A few years later I realized that the Japanese had released a second version of the set on gold cds, same music exactly. I tried like heck to get one, didn't find one . . . kept getting close and someone else either outbid me or got there first. Then years later I saw a set on amazon one day for 100 bucks. Grabbed it, hoping it was legit. . . it arrived and was and it became my go to version.
Then a few months ago on a jazz bulletin board I frequent someone mentioned that Tower Records Japan (one of the only Tower Records still about) was releasing a really limited edition (only 1000 sets) on SACD of the tape source Mosaic Records used for their LP set (the master tapes used for the US cd set were apparently were lost). I scrambled, checked with those I knew who were most savvy at getting things from Japan and found I could use the Proxy Service from cdJapan to possibly get a copy. That worked, and my copy should be here tomorrow.
In theory I could sell one or two of my other sets. Probably won't for a while.
And you got your copy from the library. Wow.
Right now
Bebel Gilberto's tribute album (newly released) of her father Joao's material, on cd: "Joao" . . . .

In from amazon
Followed by
Stevie Wonder "Inner Visions" Audio Fidelity gold cd

From the shelves