Pluspunten
Most of the work and projects are very interesting engineering solutions. A person can learn a lot from others that are interested in sharing their knowledge. There are some friendly and helpful people. There is a good work/life balance (very few project demand overtime, but it is available if a person wants it) and the compensation/benefits seem to be on the same level for other defense companies.
Minpunten
One is that it is a missile defense company, so note that you will most likely work on projects that deal with the government, need to deal with classified information, and deal with the idea of working on something that will harm or kill others. Also since there are no other major engineering employers in Tucson, there seems to be a problem with the employment pool. The problems include lack of motivation for people in other parts of the country to relocate here and a bottleneck of good talent where it's difficult to move up the ranks with so many senior people camped out in the same position for years and years and years. The work environment is not that friendly in general and is competitive. It also seems like raises and promotions are more due from a "popularity contest" model than from a straight "work completed" model. And since it is a big company, you do have a number of people that "coast" where you could say the "20/80 rule applies (where it seems like 20% of the people seem to do 80% of the work).