Pros
Good atmosphere overseas, co-workers are like family almost. State-side, it's like any other job. Pay is good considering you don't need to already have college. You'll even still likely be making more when folks have just got out of college. If your job translates to civilian life, it can be easy to get such a job. Free education available. Potential for travel
Cons
Mandatory training that is totally unnecessary/doesn't exist in civilian world. Depending on your job, might be a higher chance of being killed than in the civilian world. You usually don't get much or any choice in where you're stationed. All your friends you made will either move to a new base or you will and probably never see them again. Sometimes you work 12 or more hours a day for 5-7 days a week months on end.