Point of order. Let the record show that Battlefield Earth was the worst novel written in the history of mankind. Trees killed themselves to keep from being made into that book. (Actually it wasn't a bad story idea. It was just a novella's worth of story spread over an Atlas Shrugged number of pages.)
Actually it was a trilogy crammed into a single novel. But then Hubbard was not the greatest of writers. I actually lost dozens of hours trying to read his Invasion Earth series. What a crock o crud.
I liked it, and was entertained the whole way through. Now Hubbard's Mission Earth was a different story -- as you said an interesting idea, but spread across ten boring novels and mixing himself up with the hero (including the long ocean cruise). It is a waste of perfectly good trees. If it were an e-book, I'd say it's a waste of perfectly good electrons.