Pros
You're mostly working with nice people who all love the arts in some capacity. Has a professional atmosphere (not laidback like a small theatre company you'd find in Brooklyn), but there's always some exciting event going on. It's easy to get to know others. Very hands-on work--you're not pigeon-holed like at a larger company. It was a great place to intern and work right out of college. I learned so much.
Cons
There was a lot of restructuring going on when I was there and they were trying out a lot of new ideas, so there were some positions like mine that were going to be made permanent that weren't. As a non-profit, there's fewer chances for job openings or promotions into higher roles--though they do try to recognize people who have been putting consistent effort into their positions with a title change/some perks.