Pros
You cannot ask for a more exciting company to work for. SpaceX is revolutionizing space travel and potentially playing a major role in altering the path of humanity. Every employee plays a major role in this mission and truly feels like they contribute to the overall goals of the company. The company has a very flat structure and it feels like everyone is on the same team. Even upper management is very approachable and always open to listening to what a person has to say. Typically, managers are selected based on their knowledge and technical abilities rather than their capability to manage others. While this could oftentimes result in a chaotic work environment, the fact that every employee at SpaceX is exceptionally talented at what they do and most have the know-how and work ethic to get the necessary work done with minimal instruction makes this type of management work for the better.
Cons
A lot of hard work is expected from everyone, and employees can sometime work long hours, especially during certain crunch times. Fortunately, management (at least in my area) seems to be very understanding of each person's needs and is willing to work to find an arrangement that works for each person as long as they are able to put in the required work.