Vantaggi
If you are a junior, out of collage, Microsoft is a great place to start your career. Lots of smart people and mentors to learn from, lots of trainings and resources. Good pay and benefits. No major disturbances.
Svantaggi
After senior (63) and above, you spend most (literally easily 60%) dealing with politics, making sure you look good, watching out for yourself, covering your back, building alliances. If you choose to stay blind, you may survive if you have good management and they do these for you. Otherwise, no matter how good you are, how much great work you do, you may find yourself thrown under bus very fast, very unexpected and even your manager may not be able to save you. Politics are everywhere, don't get me wrong. However, since only people highly political can survive, senior and above is dominated and ruled by people who have their political empires and what matters most (and sometimes what only matters) is where you are in this political map. A minefield for technical people. It also kills your technical savvy by time and makes you irrelevant for the rest of the industry. If you choose to stay at MS at senior levels for extended periods, make sure you are still marketable or you become the slave of this system.