Pros
Elastic is a company that wants to be a great place to work and be very successful. They are very determined to grow and be successful and have hired a management team devoted to that goal. They are looking for people who 'live to work' and if you get on board with that there are financial rewards available. Good compensation, no bureaucracy, flat structure means you get to meet everyone.
Cons
Elastic is at a crossroads where the desire to be successful means the old culture of being a great place to work is not as important. Elastic is led by very driven people who think nothing of 100 hour weeks and you are expected to follow suit. This is a place for workaholics and if you put work before all else you will love it. If you like to take leave (or a couple hours off on the supposed shut it down days) and arent able to 'always be on' this is not a place for you.