Genuinely comparing Watchmen to War and Peace would be a good example.
War in Peace is often considered one of the "greatest novels ever written."
Watchmen is often considered one of the "greatest graphic novels ever written."
I haven't had the opportunity nor the dedication to read either, but it seems that whether you want to compare the two depends on your evaluation of the relative merits of the medium of the novel vs. the graphic novel.
Do you view the graphic novel as simply an inferior medium, or is your rejection of such a comparison simply a result of your lukewarm analysis of Watchmen?