Pros
No other company can match the coolness factor of SpaceX. Helping to build rockests is an incredible experience and all employees have a passion that energizes the entire work environment and makes people excited to come in every day and work long hours. The average age is also pretty young, which not only adds an energy factor, but also makes health benefits extremely affordable (not that the company age discriminates, I think more young people are drawn to it). Gathering outside of mission control to watch a launch is another awesome benefit. In no other industry is the result of hours of hard work seen so dramatically. It's a lot more exciting than watching a shipment go out. Compensation and benefits are very competitive (at least for supply chain). I came to SpaceX straight out of college and the base salary was higher than any offer I got from companies like Cummins or 3M. On top of that the stock award plans are very generous, and benefits are free for the employee and very reasonable for spouse and children. Most jobs are in the LA area so living expenses are definitely higher, but overall the compensation is great.
Cons
Yes the hours are long, but everyone knows that when they sign up and it's a lot easier to work long hours when you're passsionate about something. What gets me down more than the hours is the somewhat vague and nebulous nature of some of the work (this is specific to supply chain by the way). Sometimes it is not always clear what exactly is expected or whether or not we are doing a good job. This has improved over the last year, but it definitely can be stressful.