I apologize that I didn't address HC-110. I don't use it, so didn't mention it. I didn't, however, mean to imply anything about it by not mentioning it. Okay, I just ran a circle around myself 🙂
HC-110 is an acutance developer. I don't know where it rates re: Rodinal, but you'll get acutance, and one of the reasons why that particular dilution is popular is that, with decreased agitation and extended development times, you get very nice compensation.
In fact, many of the comments made about Rodinal in terms of acutance, compensation, stand development and edge effects also apply to HC-110, it seems. I just don't know whether it's got more or less acutance. Both are excellent all-around acutance developers, that give sharpness without going hog-wild with grain (not that you have to go wild with grain with high acutance - pyro devs being the counter example there).
allan