Pros
Pride in working with a small group to do extra ordinary things. High level of technical and operational compliance required and trained into everyone. If you put forth the effort to learn push your qualifications, you can achieve higher levels of leadership and responsibility within the command. This increases your chances of getting promoted. In a way you can control your own advancement opportunities. You work with advance technologies and get to make an impact (though mostly unknown impact) on national security. Beside the base pay for your rank, you also receive extra Submarine and Sea pay related to your rank and time at sea and on submarines.
Cons
You will spend a lot of time working on the Submarine; days in port can be long depending on what needs to be done. We try to work for 8 hour days inport, sometimes that does not happen and you can work 10 to 12 hour days. No overtime pay in the Navy. Then, depending on manning and security requirements you could spend the night on board every three or four days standing duty. Then when the ship is underway you can be underway, submerged for a long time depending on mission. For example, on one deployment we were submerged for 58 days, another was longer. We do have the ability to email home, but depending on mission requirements, email transfers may not happen for weeks at a time. So you can be out of touch for a while. This separation can be hard on families. About 10 years ago we had training on taking care of our families, and the instructor put out that at that time the submarine force had the highest divorce rate either in all the military or the entire Navy, I can not remember. You must be mentally strong and a good ability to adapt and deal with separation and confinement to work on a submarine. A good sense of humor is good too.