I have to disagree with you on this one Bitt. I wonder how many teenage boys and girls during the 50's and early 60's, the "Golden Age" of Sci-fi, became enamored to reading on just such works. Certainly moving up to more "literary works" but these were imaginative and exciting for the time. I know how much I enjoyed reading them then and now. In his hayday Heinlein was an absolute master at his craft.