Pros
From the moment you start working at Morgan Stanley you will be impressed by the number of top talent they have at the firm. For a large multinational bank, their technical systems are impressively agile and up-to-date. The employees clearly like working there and hardly suffer from a stagnation in skill-building. I was constantly challenged to push myself harder every day. So unless you're a cruiser, you might want to seriously consider Morgan Stanley Montreal as a very viable tech shop to work in.
Cons
Since the Montreal office is purely a tech shop, you will be separated from the business units. If you're looking to work closer with the business you will find it an uphill battle here, but not impossible. You'll probably still be on the phone with them (often way longer than you'd ever want to), and eventually if you build a strong enough case for it, you may be sent to business offices around the world (perhaps even relocated permanently), but it can take a while for any of this to materialize. MS has become noticeably stingy since the financial meltdown (even compared to much smaller firms), so expect some budgetary politics to play in, including, infamously, the painfully noticeable drop in annual compensation. If you're a pure techie, you may also find yourself doing so many things that are not part of your core interest, e.g. filling in lengthy documentation meant to gain senior mgr approval on any changes. Sometimes you may be wearing far too many hats, as well.