Pros
You will be forced to think big and innovate beyond your limits. You will be pushed to grow as a leader throughout your tenure. Limitless potential to make change. Relentlessly high standards. Take any number of leaves when you feel like. Work from home whenever you want. Come to office when it suits you, leave when you feel like. As long as you make sure you deliver results. You'll be forced to "own" what you work on. Great internal engineering culture. If you join as an SDE, your manager will either be an L5 or L6. Many of them are extremely smart and will propel you to grow. Many won't be as effective. But the good thing is, you can do it yourself. You will have enough independence to make an impact and grow in your career. In fact, you are encouraged by the company to do projects outside of your day-to-day, work with other teams for short durations, have mentors from different organizations etc. ALL L7+ managers I've interacted with have been highly competent and sharp. These are the folks you will look up to and seek to learn from. You can't bullsh*t anybody. You will be found out.
Cons
Teams in amazon are very, very independent. So much so that some of them might as well be in a separate company for all intents and purposes (some of them technically are). So there's bound to be bad teams and good teams. In the good teams (which I believe would be most of them), the high standards and expectations push you to transform yourself into an extremely well rounded Leader+Engineer. But, the same standards can crush you if you aren't smart enough. If you're having to work 10-12 hours a day to keep up/stay ahead of the curve, then you aren't smart enough.