Funny this topic came up!
I am (still) in the process of organizing my books, and came across some of these. "Back in the day" I got much enjoyment out of them, and did learn a great deal. NOW, I never look at them, and actually forgot that I had a few. At this point, I am not sure if I am going to keep them, ,or pass them on to someone else who will enjoy them. I'm on the fence, but leaning toward putting them in the "go" pile.