Dune

[SteveFoerster]

That said, anyone who's read the books knows that the experience of the source material would be fiendishly difficult to get across on a screen.

That's true.  The best evidence is the first version of the film.  It didn't come across well.
Dune (1984) - IMDb

David Lynch's movie has its merits, but I would certainly agree that it's more easily appreciated as a separate work of art from the novel.