Pros
Elon advertises his goals, then he executes. Doubters to date has been proven wrong. We plan to transform humanity into a space-faring civilization, starting with the colonization of Mars. In my view, working at SpaceX is a once-in-the-history-of-civilization opportunity. Exciting, fast-paced, and stimulating work environment. I love my job. Highest caliber people I have ever worked with. Rockets, spaceships, massive R&D. SpaceX is a tech paradise. Excellent compensation when factoring in equity and benefits. Responsibility, accountability, and authority are pushed down to the lowest level possible. Awesome parties. Great food.
Cons
Maintaining work/life balance requires a conscious choice every day. I used to be limited only by my own ability to execute. As SpaceX has grown, our business practices have gotten in the way of individual contribution. (competition between R&D and production, more management layers, larger teams with difficult communication pathways) Southern California isn't for everybody. (traffic, housing costs, taxes, pollution)