I like both, but I've always leaned toward science fiction myself. I have an easier time finding deep and thought-provoking stories in the science fiction genre, and I tend to prefer its more emphasis on exploring what its possibilities mean and using them to examine ourselves.
I like both but I find better stories generally in Sci-Fi. It's great when a series has bits of both, like Final Fantasy, which changes hands from Sci-Fi stories to fantasy from game to game.