My wife has held onto them like they were family heirlooms. We are cleaning and clearing out accumulated stuff and I pointed out that there is the cd-rom library now and that the society has made revisions and really doesn't WANT us to be reading the old stuff. She said that even though there have been changes to the teachings, the wrong understanding served its' purpose at the time. I said that she could explain that to the people who died before blood fractions were viewed in the present "light."
Anyhow, disposing of books that we will never read felt great! And she was in agreement!