Pros
It's tough to put a blanket review on all of AWS, since it's such a huge company with many parts. I'll leave my honest Pros and Cons with my experience. The schedule for an SDE is very flexible. We never had a set time to get to work or to leave. As long as you are getting your work done is what matters, AWS is very resourceful and will have all the things you need to do your job (for the most part), so at no point will your team be missing an application to move your projects forward (I've worked at companies where we didn't have the resources). Honestly, the best part is the pay.
Cons
They may tell you up front that you should not be working longer than a 40 hour work week, but that is just something they are required to tell you. Most of my team members would leave work to go back home and then continue working from home. Whatever they want done will get done, whether it harms your mental/physical health or not. Challenging is not the word here, work horse is a better word. I found the leadership to be subpar. I've worked with great leaders in the past and the AWS leaders to not have well developed people skills. Every job has challenging and tough tasks, what makes these tasks easy or difficult is how the leaders above you motivate you through the tasks. I found the leaders to have very little empathy and high egos. There is a actually a cultural difference as well. There are many foreigners that work at AWS who's native culture is all about working. They take pride in working 60-80 works. I'm not against hard work, as it builds character, but their is a limit. You shouldn't live to just work. You should work hard but enjoy life. Work-life balance was almost non-existent. If you don't come from one of these cultures, good luck.