I'm a guy, am also big on erotica/text-based porn games. Honestly I always found erotica way more stimulating than videos or pics.
To add on to what others have said, I wonder if erotica isn't the worse kind of porn in regards to how it effects us, because literature messes with our imagination more directly than just visual and audio stimuli can. Videos tend to be repetitive and and simple. It's also immediate, so if something disgusts us about a video we tend to quickly click off of it. Words, however, are seemingly more innocuous, so it leads us gradually slip more and more into more extreme fantasies without offending us as much as videos, and therefore probably lead to increased insensitivity.
I'm on day five right now, and I'm not even thinking about the fantasies or stories I've read. I know they'll arouse me and I want to only be aroused by the real thing.
That's just a thought.