I know that everyone has problems with David Lynch's 1984 version of Dune, but after seeing the television version that adds some scenes, it's grown on me. I never understood why until I saw the new SciFi Channel miniseries. It was the acting. They had little to work with, but they were fascinating. The new miniseries gives the book a much more proper story treatment, but the acting falls short. My best example is the Paul-Feyd contrast. Although, Kyle McLachlan seemed too old to me, he and Sting made excellent opposites in the Lynch version. The two actors cast in the miniseries looked so much alike and were both so wooden to me that it took me half the movie to be able to easily tell when Feyd appeared. As has been mentioned in other comments, the rest of the cast is good, but the 1984 version just had such a great cast that the acting is tough to beat.
I wish that the 1984 cast had the miniseries treatment to work with and it would have been grand. Perhaps after several viewings the acting in the miniseries will grow on me. All in all, it's nice to see more of the book's depth filmed.