I did the Ho course and found it generally helpful.
There were a lot of lectures and knowledge-base review was a big focus. But in watching the public mock orals, people weren't floundering because they lacked confidence or speaking ability ... they were sinking because they had knowledge gaps. Over and over, it was knowledge that was short. The oral is a test of judgment, but knowledge is a prerequisite.
I did the 2-day course followed by one of the must-know cases sessions. Having 4 straight days of intense, dedicated oral board study with lots of practice speaking with strangers (and listening to strangers screw up), was useful.
The one thing you get at these courses that you can't really get elsewhere is that opportunity to watch other people perform well or poorly. That helped me pick out small things (mannerisms or ways of speaking) that I was doing well or poorly. All that said, I didn't pay out of pocket for either the course fee or the travel. I may have been less satisfied overall if I'd been out $3K for the experience ... but then again, $3K isn't much in the grand scheme of things if it helps ensure a pass.
If you do go to one of these courses, be aware that they are attended by a skewed-toward-failure group of people. Lots of people who have failed previous attempts or speak English as a 2nd language do a review course. If you're clinically and academically strong (aren't we all?
), you'll feel like a rock star watching them bone things up, but don't get overconfident, because it really is a small pond.