I'm going to agree with the mass majority here.
For business, I have a domain related email, so they remain connected in the buyer's mind.
For regular email not yahoo related, I have a domain related email that is a family domain, because I know it will still exist in the morning.
However, I do have an email with another major online provider, and it works quite well - the name may be unusual, but that is also the name of my business, so it is memorable and useable and in the art business, an unusual email means nothing, except to highlight that person's creativity.
So when artists contact me, and have unusual emails, I think nothing of it.
After losing one account here due to an arbitrary violation for a quite reasonable answer, and losing another that I had literally had since you started Yahoo mail, because it got hacked, I didn't know the new password, and when I contacted support, their solution was to delete it. Gee, thanks for the wonderful help.
So while I will play on yahoo, chat on yahoo, play in Yahoo answers, I don't trust yahoo with anything of any importance.
Oh, and FYI - your arbitrary violation system makes this very question in violation - it encourages chatting, and is clearly a solicitation.
But I understand you are above your own rules.
If this answer gets a violation for any reason, I will be on the phone with Yahoo headquarters, because I very clearly answered the question as it was posed.