Pros
I found that I go to work with many brilliant people. It felt like the business was going well therefore funds were available to build large-scale projects that make a difference. Working remote, flexible schedule and unlimited vacation (to a certain extend) allow for work/life balance. I think the flat hierarchy and autonomous teams make it a good place to start your career and grow to a certain level. However, I would recommend taking your experience somewhere else before you feel the cons listed below outweigh the pros.
Cons
I think a handful of brilliant jerks overshadow the masses of brilliant and diligent people. I felt senior leadership and HR turned a blind eye to sexism and discrimination minimizing events that might have been reported to them. This seems to not only overshadow the well-intentioned people that are trying to make a difference but actually scare them off. Because of this, it makes me think women will have more difficulty in thriving in such an environment.
