Pros
I like working at Amazon because it gives me a stable job while learning very beneficial skills to help build my career. The flexibility to find another job within the company and move internally is something that should not be undervalued. The quality of people I have met working at Amazon doesn't compare to my previous employment experiences. Most people who work at Amazon have something they are striving for and are taking advantage of the many career building resources offered by Amazon. I look at it as you are who you surround yourself with and I like being surrounded by the people I am surrounded by at work.
Kontras
Some of the jobs may have schedules you don't like all that much, especially entry level positions but if you always have the ability to look for another job and move to a position that has a schedule more to your preference. I ended up doing this after a year and a half.