Pros
Great workout. Fast paced. The union takes care of you. I worked for a year and a half in a supervisory role and it worked out well for me - better pay and less monotonous. It got me through the first year of college, which is what I was there for. If you're in it for a career, going the management route is a gamble. You could rise up the ranks and make great pay with great benefits, but by losing the backing of the strong union you really take a gamble because the company can screw you. If you get hurt they put up roadblocks to acknowledging it. If you stay union you can stay their for life and eventually earn a decent pay, enough to raise a family and it's a very secure job. Your pick.
Cons
Hard work. Crappy pay the first couple of years.