Avantages
Lots of opportunities to rotate into different areas of the company. International company, lots of resources and good process guidelines. Great place for a young person to learn the ropes from older and retiring engineers. Lockheed puts a lot of emphasis on hiring a diverse workforce.
Inconvénients
While Lockheed tries hard and implements good anti-discrimination policies, the culture is still pretty conservative, especially at the higher levels. Granted, things have changed a lot since the 90's and much more diverse people are climbing the ranks into top management. It still has a way to go. Also, if you don't like the aerospace/defense industry, then none of the defense contractors (Lockheed, Boeing, Raytheon, Northrop) are a good place for you to work.