Vantaggi
First of all, I worked here a long time ago when there was more spacecraft design in Sunnyvale. (2008) They moved a lot of that after I left and I'm sure things have changed some. Engineering, for the most part, is king on campus. Most managers have a strong background as engineers which gave me a sense that we're all part of a team and bringing our experience to bear on the problem. As a young engineer I really enjoyed the cool headed offhand wisdom some older engineers would drop around a conference table. I enjoyed the need to get things right. Most things we worked on were "high value hardware", so you'd really like to do things right, not have "anomalies" on orbit. So it's fun and challenging because you've got to dig into everything that could go wrong and make it so it positively can't happen. It's fun and a little other worldly to work next to a towering satellite in a clean room high bay. Fun to see your designs come to reality then know that they'll be on orbit for the next 30 years. With so many people on campus we could field 9 soccer teams. Good fun one day a week to meet directors and engineers from other departments on the field. I did everything from 60-70 hour overtime weeks, sometimes meeting at midnight with the customer on "in flow" projects, to pretty normal office weeks. Work life balance is up to you. For me I could generally bite off as much as I wanted.
Svantaggi
There's a rumor that some managers weren't great at engineering and thus "failed up to management". I might have experienced some of this and it gave me the opposite feeling I listed in the "pros" section. Many "flight" projects are "legacy" and thus very slow moving. You can't just design something new and launch it into space on the government dime. So a lot of what gets done is certifying, asking people to approve, tending to flight details. A flight design could take years to get launched. However, I soon found that designing manufacturing hardware was faster and thus more fun. Still, it could easily take 6 months+ to push designs through review boards and such. Some aspects of satellite design were pretty top down. For example, each team was given a weight budget. If they made their budget everything is okay. As a designer I could have shaved off some weight pretty easily on a few projects. I typically requested to do so, but was met with indifference or opposition because we were already under budget. If it were less top down I'm sure lots of little improvements could be made. I see the reason for this but was a little annoyed at the time not to push this high performance hardware to "high performance".