Pros
Georgia Tech is really all what you make of it. You can have the best time if you're in a good program with a good advisor; on the other hand, you can have a terrible time if you have a terrible advisor. All in all, though, all of the engineering programs are top-notch and you will (if you make it through, that is) end up with a quality, respected, and solid education in engineering fundamentals. If you want a PhD, Georgia Tech is a good place to do and living costs in Atlanta are fairly cheap. Try and figure out what you like about it.
Cons
The place is very high-stress but is manageable with good time-management. Some of the departments (PARKING especially) are notorious for making students' lives hell, but if you know how to work the system you'll figure out what to do and what to avoid in order to avoid headaches. It is absolutely necessary to have good time management skills; otherwise you can end up getting very far behind very quickly. There is kind of a sense of depression and stress amongst the students here but there are still plenty of ways to keep yourself happy. Try and avoid the parking department.