Pros
The most inspiring aspects of this job are the ability to learn a lot of new stuff quickly and the reality of seeing your work result in a finished vehicle. The work environment is fast paced and sometimes there are major changes in direction along the way, but it is great working on programs that last months or years vs decades like other aerospace projects. Through my 6 years at Spacex, I quickly developed new analysis, design, manufacturing and project management skills because of the diverse workload. Spacex is less about building a giant system to make sure that any idiot who comes to work will be able to turn the crank, and more about putting trust in smart individuals to make good decisions and get things done. To ambitious people who want to do relevant work, this is great situation. Those who just want to turn the crank need not apply.
Cons
With great power comes great responsibility. Work obligations can get in the way of personal life activities, but not to the point where I think this is a major drawback. I think a reasonable person should be able to manage the demands of SpaceX work and their personal life, although some former employee reviews suggest otherwise. The company has grown a huge amount, and critics will say that this has brought undesired changes. I'm honestly glad to be working at a successful company that is dealing with the challenges of how to manage growth instead of having to do layoffs.