Harmony Heights is an interesting place in that it serves the same clinetelle as the therapeutic boarding schools that we do know to be abusive (middle and upper class families). And I've heard stories of girls who interviewed at Harmony Heights who didn't get in who ended up in Madonna Heights (a confirmed hellhole paid for by your taxpayer dollars).
But as for the school itself, it is what it is. Generally, the school is paid for by wealthy local school districts who would rather pay for an expensive boarding school for a few years than educate an emotionally different teenager themselves. It may not be abusive, at least to the extent that there have been no reports of abuse, but the program is still a symptom of the larger problems that affects the industry itself. While they'll only take girls who want to be there, you wonder what the forces may be at work that encourage them to be there for three or four years at a time.