Pros
Learn a ton, be surrounded by some of the brightest people in the industry, have an easy time interviewing for your next (higher paid, lower hours) job, truly have a seat at the table, have more responsibilities and accountability than you could possibly imagine as an FA
Kontras
Unfortunately it all comes down to your manager. If you win the manager lottery, it can be a rewarding place to start your career. Otherwise, expect to work at least 60 high-stress hours a week. The reports about crying at your desk are unfortunately pretty accurate. Please consider how much you value work-life balance before you join. Expect to work a good number of weekends, even if your manager says it should be "highly uncommon." Amazon has so much potential to be a great place to work, but unfortunately management can totally ruin that. YMMV.