Not sure about the aides and substitutes. The information was put out by the district, not by the union, so I think its safe to assume that its reasonably accurate.
That I don't know about. I'm not sure what kind of difference that would make. At one time, I worked at a place that had a union, so I know a little how both sides can make it sound like they're the party to be pitied. So much depends on your perspective and what you're trying to accomplish. Keep us updated.