Pros
I've never had a greater work/life balance than I've had here. There is a large contingent of former Navy/Marine who cherish the adage that as long as the mission is first and taken care of: Get outta here!
I can't speak to every code here, but ours is pretty supportive of the little things that can be pretty nagging at other companies: Your laptop sucks? Here, lets get you a new one. Your computer sucks and is 4 years old? Here's a new one. Your kid is going to be in the hospital for a month? Here's some extra leave we are able to donate and/or work from home, man, we'll figure it out. That's what makes you want to stay forever.
Want to spend 2 weeks on a ship? No problem! We'll get you on one. (Although, for a lot of people, they never want to do this again)
My old manager would remind me that you never work for the government for the pay and that is very true here. While outside of gov life, I'd probably be making 10-15k more than I do here, I don't think I'd be as happy. I don't think I'd be as free to work on side projects (or the opportunity to move to someone else's project) or to just come up with my own. Granted, that last one is a bit harder, but it's not impossible as it would be at some defense contracting companies.
If you are in the need for a Masters or would like extra training/classes/certifications, I don't think I've ever seen anyone turned away from an educational opportunity. Ever. Now, asking for a sabbatical to finish your Doctorate is one thing, but for the most part, getting in to NPS or a local school to get that M.S. in CompSci is almost a given and you'll get support from the top down, but as long as your educational goals fit into the SPAWAR misison, you're probably going to get your classes.
As for travel, I'm not in a regular code that sees a ton of travel, but there are the obligatory trips to Washington D.C. and the odd trip to a site your team supports in a joint capacity that's in Florida or Washington or Philly, but you make it what you want of it. If you want to go, there will be opportunities for that, but if you don't ever want to go (and your job doesn't call for it) you could probably work here travel free.
The views are amazing. If this were Intel or Lockheed or Google or whatever, their property would be $3,000,000 sq/ft for where some of the SPAWAR offices are located. The parking lot by Building 600 overlooking the Pacific is probably worth $40,000,000 by itself. The cafeteria on the 3rd deck at HQ overlooks the entire San Diego harbor and is gorgeously relaxing. However, if you get stuck in Old Town, I am sorry for you. Once inside, some spots are OK, but from the outside, yes, it is basically walking up to a 1980's warehouse.
Cons
I've seen it go fast, I've seen it go painfully, painfully slow, but sometimes the bureaucracy that is a government R&D/O&M agency can be horrifically slow. The amount of legalese and doctrine and policy and guidelines that need to be followed can take your super cool startup idea and squash it in the mire that is SPAWAR approval.
Things that would be decided and started on in 1/2 a hour meeting in Silicon Valley would take 6 months to get approval at SPAWAR. It makes no sense for a command that prides itself on cutting edge technology and services to the warfighter; believe me, I know there is "getting it right" and there is "getting it right now" but SPAWAR is years behind their commercial counterparts who work on similar projects. There is sometimes no difference between $100k projects and 5 Billion Dollar projects on moving things quickly, but it feels like the umbrella of policy driven management styles clash with the technology driven environment here.
As far as pay, if you commit to putting the mission first and succeed in your tasks you'll be given the government standard raise. It's not going to be a lot. At all. But that is the nature of working for the government and you should be prepared for that going in. Sometimes, you'll get in at a certain rate and it will feel like you're stuck there forever. This is by design.
Perks: There are basically none. You may get to take every other Friday off. You may get a shiny new MacBook. You might get a parking spot. You may get a desk built post-1967. You may get cell service down by Seaside if you are within 40ft of certain offices. (Oh yeah, if you work in a Seaside office, AT&T, Verizon, Sprint has ZERO coverage if you are lucky enough to take your cell phone to your office).
If you bust your butt, you will probably get a few team/individual awards and these are NECESSARY to move up. But you want to work for SPAWAR, so I'll assume you're pretty good at what you do.