Pros
The company has an awesome, worthwhile mission, and the workforce comprises top talent. People always find it interesting when I tell them where I work. The pay/benefits are decent, but not great. For those who started a few years ago, the stock options have more than made up for mediocre pay, but that may not be the case going forward.
Cons
Expectations are based almost exclusively on results and take little regard for effort. That might be an ideal metric for manufacturing or even engineering where if you apply enough brain power, creativity, and time you can almost always get results. But for other functions, where results may be determined by factors wholly beyond SpaceX's or any SpaceX employee's control, this can be unreasonable.