WOG the current bonds are supposed to be water tight provided they're signed in conjunction with the current AWA. This hasn't happened in some cases.
I don't think there is generally a problem with other companies if you haven't paid a bond, though I've heard that Qantas doesn't like it and Cathay will pay it for you. I guess the problems occur when the airline industry turns to **** and you find yourself trying to get your old job back. There were quite a few who came back to SAPL when Ansett went down. I guess it's matter of whether you're comfortable burning bridges as you progress.
PS say hi to our wives from me and my animals