Pros
Highly regarded firm. Excellent reputation. Great experience and lots of intelligent people working for the firm. It's an excellent opportunity for anyone who can get a job there. In my experience, lots of firms say they hire smart people, but Morgan really did hire smart people. Was a very professional environment. People were very dedicated to their jobs and seemed to value having a role with the firm. Potential for some good Sr. Management interaction depending upon the position you're in. The offices were fairly comfortable and well laid out, and the headquarters is pretty central in mid-town Manhattan, although there are offices elsewhere in NYC.
Cons
It can be a very stressful environment. I encountered as many nice people as I did jerks. The firm can be very difficult to navigate, especially depending upon your department. People in front office roles seem to be held to a much higher esteem than people in middle office or back office roles, regardless of how big of a revenue producer that individual or their department is. As for work life balance, that also depended upon the department you were in. Some people had managers who were very laid back and didn't mind employees working from home or needing to take time off, while others were far more uptight. At Morgan, much of your experience depends on who you work for.