Vantaggi
Many of the entry-level staff are amazing people and great to work with. If you get a good supervisor (usually a "coordinator" or "director" depending on the department) you'll get good training and have at least a decent experience. Hours can be flexible during slow times (ie, when it's not a contract campaign.)
Svantaggi
The bosses here are often absolute, power-tripping jerks. It wasn't unheard of for them to be manipulative, abusive or even commit Unfair Labor Practices - the kinds of violations of labor law that unions are supposed to prevent. Sometimes bosses would yell at you just for asking a question! Long, irregular hours and tons of travel. Lots of bureaucracy - conference calls, useless databases, etc. Additionally, if you're a progressive person looking to really empower people, look elsewhere, because this local is all about top-down decisions and using members as tools. Low pay compared to other labor unions (though this is someone understandable considering how little the members are paid, and therefore how much they can afford in dues.) Nepotism is also pretty rampant - and I'm not talking about well-liked member leaders being brought on as staff; I'm talking about extremely well-qualified candidates being passed up for existing staffers' girlfriends.