I understand, I can be quite vain myself at times.
Oh yes, I have found quite a lot of people cannot speak clearly. I especially hate meeting and group situations too. Don't you just hate it when someone is talking and then they look to you for an answer or to pick up on the discussion and you don't know what they asked or are talking about? Like last Wednesday I was in young adult bible study class, since we had a new teacher I asked him on multiple occasions in the beginning to speak up because I couldn't hear him. Then he'd talk and ask me a question and I'd have to tell him that I didn't hear him. I don't know about you, but it sure makes me feel stupid!
The amplification of background noises is definately a con on the list, because like you, I can usually hear that just fine. There are a lot of days that no matter how clearly someone is speaking, all I hear is muffled sounds, ringing, and/or echos and a hearing aid would not be able to help that, it would only make it worse.
I've read that the invisible ones are supposed to allow the hearing to be more natural so based on that I would expect it not to just be amplified sounds but you never know.