Pros
Work/life balance is good. I rarely worked past 5:00 PM and can count the times I worked on the weekend on one hand (over the course of 4 years). For the work I was doing (which wasn't very technical) and the amount of time/effort that went into, I was paid well.
Cons
For me, pretty much everything else. The work wasn't particularly interesting, and when something interesting did pop up, it was usually allocated to someone purely based on office politics. Microsoft is definitely not a place where you can show up as a new hire and do awesome things, it's more likely that your co-worker who has been there for their entire career will be assigned the work before you've ever even heard about it. There were also usually ~2x as many people involved as there needed to be, which only slow things down. That is especially difficult because Microsoft is a VERY meeting heavy organization, so you'll spend lots of times in meetings that 1) go over, 2) get rescheduled repeatedly, and 3) are 90% irrelevant to your work. Honestly, there were a lot of other things as well, but I don't have 2 hours to write this.