Pros
While originally there was little to no organization of the students in the department, and no accountability, a new boss took over the students and drastically improved it. Working at the helpdesk requires real work now, but you can learn a lot and I actually received interview requests from two very large firms that high a lot of Swarthmore alums. Very supportive environment, with a defined schedule but a lot of room for flexibility if you find someone to cover for you.
Cons
If you work at the helpdesk, it is very difficult to do homework. While there are fewer of these people now thanks to the new boss, you still get some people who will yell at you for something that someone else did which is unpleasant. Pay is good for work-study, but still very bad compared to what you actually deserve to earn once you've had some experience.