Pros
Amazon feels like a massive startup incubator with unlimited free AWS credit. I started my career at Amazon as a Software Development Engineer intern right out of college. I was given an open-ended problem to solve by my manager at the time who taught me a lot about the Amazon culture and how the leadership principles apply to the work we do. I had a lot of freedom to try things and explore other parts of the company, participating in hackathons and attending tech talks. I was hired full time to keep working on the project I started as an intern. As the years went by, there was some turnover but mostly a lot of growth in our team size. After a few years, my manager of the time left and I was offered to step up and lead the team which I am still doing to this day. Since I took over, I hired enough people to quadruple our original team size. I believe that Amazon is one of the few places where you can be trusted with responsibility so fast and be given the freedom to run your own internal startup within the company.
Cons
Amazon's model of small autonomous teams is both a blessing and a curse. The work environment is chaotic and there is no standard operating system that everyone adheres to. Another downside is Amazon's culture of building everything in-house. This means that you can't import external innovations that would increase your productivity (think Slack, Google Docs...) and you are instead stuck with what the company has built. With AWS expanding its productivity suite, it is becoming less of an issue though.