Pros
The flexibility and autonomy are truly amazing when compared with the standard 9-5. Fringe benefits, like metro allowance, access to financial planning and theoretically unlimited vacation time are big bonuses. If you are ok flying under the radar and are more concerned with quality of life than advancement/accomplishment, many of the cons likely won't bother you.
Cons
The company offers such amazing fringe benefits because it's cheaper than competing with other companies on salary. Depending on your department, you will likely earn a fraction of the market rate, particularly if you work in tech or investing. Despite repeated initiatives to make compensation more transparent, few understand how the process works, who you can talk to or who makes the decision. Further, the company has very little discipline about developing and managing people -- despite high profile coaching initiatives. The majority of senior managers are long-tenured employees who joined the company during its startup stage. Few have worked in traditional settings, let alone have management training. In general, the company's expectations for employees are incredibly inconsistent and unclear, if they exist at all. There's no clear career path and managers aren't required to have set metrics for subordinates. This leads to an unhealthy focus on politics. The org chart is a mess, and the company has devolved into a series of fiefdoms. Authority rests with whomever can get the founders most excited in a given week, and this leads to a game of "who can build the biggest sand castle." Moonshots are a dime a dozen, and the company seems far more enthused by shiny ideas than execution. All in, the Fool talks the talk of an employee-focused company without actually walking the walk. The company makes a show of window-dressing with fringe benefits but falls down on meeting core needs like fair compensation, sensitive management and clear career opportunities.