Generally it is far more offensive to a man to call him a bitch as this denotes his lack of manhood.
Everyone who knows me even *this much* knows how much I loathe and detest the C word so if I am using it to describe another female ya'll KNOW it is bad... and it never ever about appearance but ALWAYS because of behavior.
The only other way I use it is like this.
"Honey, not to be a c*nt, but have you heard from that bitch about the money you loaned her?"
And I say it that way because we had already discussed the matter ad nauseum, he knew he fucked up and we both know it wont happen again, but still it is my right to follow up...
So I am letting him know with this phrasing that I realize it might be construed that I am really busting his balls, but I am not so he won't get defensive.