Ryan is probably of average endowment based on: how he carries himself, how he reacts to the Magnum news, and on the bulge he was showing in his pjs during one of the episodes (where he describes that he keeps a journal I think).
Ryan's compelling for other reasons though. He's obviously a man at odds with himself and his past (an isolated hometown culture vs. an expanded worldview culture, not to mention with being a soldier). He has a lot of growing up to do still; there's the drinking, and his obvious discomfort around Katelynn and JD (alternative sexuality peoples). He tries to cover it up by saying he's just curious, but it's very easy for me to see that he wants to know because he feels threatened (by their sexualities, by ambiguity) and he wants to know where the threat is and if it's definite. But at the same time, he is sensitive enough to be a musician, to write a journal. And I think he's intelligent enough to better himself, because he is conscious of his conflicting emotions and that's the first step usually. It'll be interesting to see if and how he develops as a more well-rounded, well-adjusted person.
I don't watch the real world, but this season interests me because they're really diversifying the "cast". There's a chance here to explore sexuality, aggression and war, dreams and life goals, religious fundamentalism, relationships with people in close quarters, all within the context of not being able to run away from the subjects (unless they quit the show, which contractually they may not have as an option).