Pros
Decent experience at the beginning, tapering off the longer you stick around. You can get experience in new technologies, but don't expect much training. Often left to work autonomously and make decisions, which can be a pro or a con, depending on the situation.
Cons
Pay is well below market average. Benefits get worse every year. Expect to work long hours and do the job of several employees. No raises or bonuses for years. Often put in the middle of conflict between managers. Upper management can be very unprofessional. As long as you or the customer never complains, management ignores you. If you do complain, expect to be given extra busy work to "resolve" the problem. HR is very little help with problems and often refers you to the intranet website instead of actually helping. You have to prod HR repeatedly to get paperwork done. Don't trust them when they say they will "handle everything".