Male - 25 Years Old
I'm an officer so I didn't do enlisted boot camp (though I did something similar), but I wouldn't sweat that part of things too much. They want to get everyone through. It's shitty, but just don't be the guy who screws over his friends, and you'll be fine. I'd just like to echo the "think this through" thing. The money is great. The job-security is awesome. The opportunities for exciting training are plentiful. And the people are the best. But if I could do one thing over, I wish I would have just considered alternatives more at 18. Hell, more than likely, I'd have done the same thing. But while I have seen the world, and done some wild stuff, it is frustrating to not necessarily be able to go back home and see my friend's wedding, or to not be able to see my sister's graduation from college. Don't get me wrong - 99.9% of the time, the military gives you the tools/money/ability/leave to do exactly what you want to do, but it's like they have always have a trump card - "we can not let you, if we choose." So I guess if I were you, I'd just think about what that entails. Like others have said, don't rush into the decision.
As far as services go - I'd enlist in the Navy, just for the chance to see the world. However, from my experiences, the "happiest" enlisted I've seen are Air Force, even though they might have the most "boring" of jobs. The quality of life in the air force is pretty sick (that's what I am), and we tend to have the nicest bases (though not necessarily in the best spots). Being on a boat for 9 months and seeing all these foreign ports sounds pretty romantic to me, but a lot of people say being cooped up and cramped for that long sucks.
Ps, I'd research more about that tattoo policy in the AF. I don't know what it is specifically for enlisted, but I would imagine it is more strict for officers, and I have a big fat one right on my wrist. No ones ever said anything. And I work with a guy (also an officer) who has full sleeves. So you might wanna doublecheck that.