I keep singles of the Miles Davis Columbia's that are also on the box sets I have, and the same in a few other select cases of keeping favorites on single CD while I also have them in box sets, partly for the artwork, partly for convenience, partly for historical context, etc. But those are all CD's. I don't have the space, the listening setup (90% of my listening is through headphones while I work), or the inclination for vinyl, and I continue to actively seek to move the vinyl I do have (time permitting).