Pros
There are some incredibly intelligent and talented people working there who make the workplace enjoyable.
Kontras
During your interview, they sell it like they're a cool startup where you you have "lots of opportunity", however there are not any real opportunities to advance your career. Exemplary employees spend years with the company and never advance, since upper management believes in hiring from the outside when new positions are needed. Management is bad, sometimes to the point of being toxic. One of the founders is passive-aggressive. Don't dare to disagree with him, or you'll become his next target. He is very critical and is willing to throw you under the bus to avoid making himself look bad. Work environment is not friendly to employees who have families, though management would deny that this is the case (without bothering to even think about that feedback or ask any questions to find out what might cause someone to feel that way). The lack of work-life balance that managers pressure you into is one example of this, another example is that they reduced the maternity leave policy conveniently right after adding more women to the company.