I work for a unionized business. There are good and bad with the union that "represents" me. I've seen several instances in which the worked would have gotten royal screwing and probably terminated, mostly because their supervisor was a rectum, if not for the union. I've also seen too many employees that are a waste of floor space kept on the job because of the union.
On one side of the coin if a person is doing the same job/job title they get the same pay as anyone else doing the same job. The flip side of that is that they get the same pay even if they suck out loud at the job.
The politics of the union also tend to stink pretty bad. One of the last times I was at the union Hall was when Kerry was running for Prez. I was offered a Kerry campaign shirt. I politely declined with no political commentary or reason, just a "no thanks". The young lady that offered me the shirt absolutely came unhinged. I'm pretty sure that if a union VP hadn't stepped between us she would have assualted me because I didn't want a Kerry t-shirt.