Pros
You will get to work on interesting projects and be a part of an exciting mission.
Cons
Your job demands 100% of you so it's really hard to de-stress and leave the work at the office. Work/life balance is not really a thing. You more or less are buying into Elon's mission and, as a result, whims. There is an absolute breakneck pace of all projects where everything is late from the point of inception. There are high levels of organizational chaos/uncertainty where the turnover is severe and important people with disappear very abruptly. Overall I'd say that it's a very young organization chocked full of super intelligent, idealistic young people. This is great, however, there is a severe lack of engineering wisdom that comes with experience. Hubris is a thing. Safet.