Pros
Salaries are pretty much at market, the company also offers some reasonable benefits and the work/life balance is well encouraged. It is indeed possible to take time off (in reasonable amounts!) and to work from home if you really have to. Morgan Stanley is a well-known bank and most of the business is done because of the "Morgan Stanley brand". The company shows a very good face to its clients, hiding how hard it actually is internally to properly manage a portfolio, correctly value it or even manage its risk. The company is surviving because of the name, nothing else.
Cons
Morgan Stanley is a company with a few very good people at the very top and the very bottom i.e company management and associate/VP professionals. Between them, you have too many people who are incompetent, spending their day in meeting rooms, playing the politics and getting nothing done. Too many people in this firm are making a full-time job trying to save their own job, finding people to blame for the things they cannot get done. It is not a meritocracy at all, the company survives by its name while, at the same time, it is run on unadequate IT systems, and incompetent managers.