Avantages
The salary I received over the years was awesome. Some of the projects were good - but I definately did not think the projects were cutting edge or very technically relevant. And in the end they did not contribute much to my resume. Pretty sure anything technically relevant was given to a younger person. In fact, after working on a java project for a couple of weeks - management swooped in to remove me and place one of the "Leadership Program" people on the team. The lawyer I spoke to told me that the person had some "other" special training that made him a better fit for the project.
Inconvénients
It is gov't contracting after all. This can make it not so stable of a career at times. We had several large, older programs shutdown the last couple of years and the company and HR management literally did nothing to help us find jobs inside the company. We joked about their "Grab Hold of Your Career" effort as being "Grab Hold of Your Rear"! After years of working hard in my cubicle I was expected to have some huge network of engineers and managers that I should work from to find MYSELF a job! Yep - that's what Grab Hold of My Career did for me! Submitting my resume to job requisitions year after year resulted in not a single phone call from anyone or an internal interview. When sequestration occurred last year - I was also expected to sit in my cubicle doing nothing (for 8 weeks!) because I had no contract number to charge to. Really Lockheed Martin? I had always been very proud to work for Lockheed Martin but it really resulted in a big zero for me. Lockheed Martin provides little to no training - so it is very hard to stay abreast of new technologies - especially for software geeks. (Go to Northrop!) Oh - also - watch it if you are a level 4 - you absolutely will not be able to move around much. Try to stay a cheap level 3 for a long as you can!