Pros
Defense work can involve interesting technologies and may involve travel. May require a security clearance, which can improve your job prospects in the engineering field.
Cons
This detachment of the company is extremely small compared to the space/airborne defense companies in El Segundo. There are far fewer projects, so you may be working on developing cutting edge industry tech, or performing maintenance on systems last updated in the 1980s. Some projects may not be very well managed, leading to deadlines with more stress than average. You may get to work on the same project for years, or be suddenly pulled off to something temporary if funding hits a critical level. Work location is clearly meant for new hires looking for their first job or locals looking for stable employment - the majority of employees are college grads or "lifers" that are already closer to retirement. Middle-career employees are scarce due to being able to find much more plentiful jobs and competitive salaries working in Los Angeles or the SF Bay Area.