To be honest, I have been collecting music for so long that I have never felt the need for any over priced box sets. I guess there is some appeal for bonus tracks, outtakes, dvd’s, and booklets.
From that list you posted a link to:
Kiss - I was never a big fan. <shock>
Iron Maiden - I have the entire studio album discography.
Guns n Roses - I have the studio album discography.
Motörhead - Not a huge fan but I have almost the whole discography.
Alice In Chains - I have the discography.
Rush - again, the entire discography.
Whitesnake - the discography
Dio - The discography