My partner is in the navy (Australian) and I totally agree with the other posters - it is definitely a lifestyle choice. You may get no choice over where you live and what projects you work on and who you work with or your working hours and holidays. Anything can change without notice. I know of people in his crew who have missed their own weddings because the boat had to sail (even though they were told six months earlier that they would definitely get the time off). That said, he does get paid well and gets to do 'fun' things at work - like being paid to play sport for a week.