Just checking the thread again after being away for awhile. Conner and Leah bite, but they're smaller birds and don't inflict as my damage. It does hurt, though! Conner's not been biting me nearly as much lately.
If at all possible, I try not to react when he bites. It can be difficult though, because his beak is like a needle clamping onto my flesh. If he grinds in, I might shake my finger to get it out of his grip, but still try not to react.
When it's over, I tell him 'no' in a firm voice. I give him the Evil Eye for a few seconds. Then, I analyze the reason for the bite. If it's him being fearful, he gets put on his bowl for a time out. If he's just being a tool for whatever reason, he gets put in his house for a time out for at least 15 minutes.
Leah is a rescue, so she's not very trusting of me. I don't react at all to her biting, because I know it's from how she was previously raised.
I've also warned visitors to my house that the birds can bite, and to please not handle them. One fellow got bitten by Leah, because he wouldn't leave her alone. She took a good sized chunk out of his finger, but he wound up apologizing to us because it was his fault for ignoring the warning.
I've noticed that my birds bite me less, and when they do bite, it's not nearly as hard as it used to be. It's an ongoing challenge to bird people.