Pros
Just read the Amazon Leadership Principles and Amazon letters to shareholders. If that describes the type of environment you want to work in, you won't find a better place. Hours and pressure abound, but directly proportional to opportunity for and desire to grow.
Kontras
Some find work life balance difficult, but that's only if you really have FOMO and can't leave any opportunity on the table. There is just too much cool stuff to get involved with and ways to make an impact, so balance won't naturally happen, but it was certainly always there for me. My daughter (first baby) was born within the first 6 months of my employment there, and then my son came right in the middle of the busiest time of the work year two years later. No one ever batted an eye giving me all the flexibility I needed to take time off as a dad and ramp back up slowly. But those who don't ask, or have a hard time getting work done during work hours might find it difficult to keep up. Lots of smart people that can make you feel stupid sometimes just by their pace and intelligence.