30 person startup means that you can make your own career path and get involved in many parts of the business. Everyone who works here is really smart and passionate about the work that they do. The "take your work seriously but not yourself" creates a really hardworking but playful culture.
Cons
The size of the company means that the workload can be really demanding. The pace of the business is also lightning fast. Some people have a hard time working in that kind of environment.