Pros
Have end-to-end ownership over building a product. Get experience building large scale distributed systems. Extremely smart colleagues. Opportunities to build systems with global impact. Writing and meeting culture leads to no-bullshit transparency that helps the company make better decisions.
Kontras
Doesn't feel like company cares about you - benefits and pay are not competitive and too much red-tape for getting simple things. Not enough gender or racial diversity. Company doesn't invest in teaching recent hires the tools of the trade - is all self-paced, leading to a sink or swim environment. Promo process is highly manager-dependent and inconsistent - managers dangle future promotions to get employees to work beyond what is reasonable. Everyone is running under tight resource constraints, creating a very political atmosphere.