One of the things I love most about the literary hop is how subjective the questions are. Oh, and the other awesome bloggers, you're great too. This question all depends on what you think of as difficult. For me Jane Austen and Shakespeare aren't difficult and Fitzgerald and Salinger are easy reads. It's a combination of writing style and and familiarity that make authors like this accessible to me. On the other hand Victor Hugo and Virginia Woolf make me want to cry big wet tears of boredom. I find their style dry and am not familiar enough with each writing era to make my experience any more enjoyable.
Fun fact: I have started The Hunchback of Notre Dame no less than 7 times. I never get past the first six pages. I have also been lurking at page 80 of Mrs. Dalloway for over a year with not intent to return to her stream of babbling pages.
I feel the same about the modern literary writers. I find Jonathan Safran Foer easy to poetic and easy to read, but Zadie Smith is lost to me. In theory I should really enjoy both, but I just can't get into Smith's style. It grates on me, and leaves me stuck in the middle of her books forever. Don't get me wrong, I'm not saying difficult is bad. I loved Les Miserable, even if it took me forever to read, and Autograph Man changed my reading habits in high school. I'm all about challenging myself and my comfort zones, and that's where the mythical "difficult" writing becomes important. Some books are about the journey and some are about the destination, and with difficult writing i'm all about the destination.