Pros
It could be an interesting company to work for as it still seems to attract talented and intelligent people, has market share and revenue enough to try new or disruptive products/services. But because the leadership of the company is feudal and constantly reverses itself, and the middle management is left to itself to create a Disney-sized theme park dedicated to "Lord of the Flies" style handling of their human chattel, none of the pros matter much.
Cons
Very little of the old company remained when I went back. The stock benefits are gone replaced with a partner level elitist group managing the company to maintain their own comfort rather than innovate or compete. Stock itself is meaningless, and the pay and benefits is marginal (both of which are not real reasons to join a company, but are part of the old myth of MS's wealth and prosperity, which is long gone.) Innovation is of course routinely suppressed and rejected. There are so many "cons" to list that this would be an entire compendium of books (for example book #22 would be "Harry Potter and the Abominable Review System that Keeps Wage Slaves in Their Place"). So I'll skip to the end: Microsoft refuses to change and keep with modernization of technology. Its hard to blame them, as IBM did the same thing with mainframes to maintain their market position and profit. In the future, you will see a time when MS executives are on the street trying to sell a CDROM, shrink-wrapped version of Windows 22/Office 2023 with the tag-line of "Its all we really understand how to make". And don't be drawn in by their lip-service to anything "cloud" or "online"...they'll revert back to shrink-wrapped product on 1.44 floppy disk given even the smallest chance trying to relive the "glory days" of their revenue heydays.