Jan brings up a very important point.
While I am all for a BAHA (obviously, since I have one!), you have to expect that it has limitations.
Chances are, you will still not be able to tell who is talking in the lecture hall because for most people, it will not restore directionality. My doctor told me that for some it does - for me, not so much. The good thing though, is that you may be able to hear the person better in the first place, even if you can't figure out where they are sitting. As far as banquets - I always have to turn mine off when it gets really loud. All it does, like most aids, is amplify the noise. I understand the BP100 might be better at filtering out the unwanted noise, but I don't have any experience with it, so I'm not sure. I do find it helps at a dinner table, as long as it's not too noisy in the room to begin with. I am able to hear the person on my deaf side. I can't always hear everything said, but usually enough that I can follow along with the conversation.
As long as you go into it with reasonable expectations I don't think you'd be disappointed.
So, you're the consumer - tell your doctor that's what you want.
Lori