Pros
Majority of people are very nice, hard working and knowledgeable about the business they're in. It can be a fun and relaxed environment because the firm still has a feel of a start up, even though the firm has grown quite large in the last few years. Depending on the immediate manager's philosophy, the company can offer flexible work arrangements and time off, when necessary.
Cons
Company has grown a lot and it's beginning to feel like a big corporation with its beauracracy and expectation of face time from employees. Senior management only cares about highest producing individuals, the rest get treated as nobody's. Support areas also don't get much management attention or support. As a result, there are many unhappy employees especially in support functions who do not bring in major $$ for the firm.