I have a very large collection of box sets which I am a bit obsessed with to be honest but rarely go for the type you mention. I prefer the career retrospective ones with loads of extra tracks. My favourites are the Sandy , Al Stewart and Ian Hunter ones. I have most of the Free Reed ones, and related.
I have the Al Stewart one- still sealed. It was an impulse buy and i have all of the albums, some of them more than once.
Yes I know - 17 albums and the rest of the 35 (?) is extra stuff.
