Pros
There are a lot of really nice people who work there. They have good training and you learn a lot quickly which makes it great for career growth and future employment opportunities. Unlike Big 4, you get to work on the entire engagement from planning to wrap up.
Cons
Some of the partners and principals who work there are literally clueless. They will sign off on any engagement despite lack of knowledge on industry and subject matter. If you are good at your job they give you more and more work while keeping people who sit around with no work to do. The firm is ran by a group of older white men who do not value diversity or the opinions of women. They do not appreciate their employees or hard work. Promotions are not based on performance or skill but passage of time. Management does not keep employees informed of things happening in the company. Morale is usually very low and everyone complains all the time. There is no work life balance. They do not value their employees or treat them well.