Pros
You get to work on some really interesting projects and see some cool equipment in the wild. There are some good managers that care about their employees but these are few and far between.
Cons
Management have no interest in change however much they might claim to. Particularly in submarines there is no escaping the outdated Barrow working culture, and some of the managers think pressuring the teams into unpaid overtime is the answer to everything. Project managers are allowed too much oversight of engineering solutions and have no accountability to the engineering leads whatsoever. My team were forced back into the office mid-pandemic for no discernible reason other than one senior manager thought it would make them look good even though we could demonstrate productivity improved while working at home Incompetent managers are promoted into senior leadership positions based on their friendliness with the heads of department not their competence in either leadership or engineering. Some senior managers are known bullies and just get moved to new positions, again often due to being mates with someone more senior.