Pros
As it is a small company, freshers will get good exposure. Most importantly who ever wants to take responsibility, will be given the chance to do so. Free and open culture, you can walk up to anyone (even CEO) if you got something you wanna share..
Cons
On the other side of the spectrum if you are an experienced professional, you don't have job security. You can be fired any time when they feel like. Personal grudges or friendship will effect your career in this company a lot. So make sure you are on good terms(i.e. talking too much with management and saying YES to everything they say/think of) with the management, otherwise no matter how good you are at your job, your career will take a dive. Lack of professionalism in the company will be irritating.