Pros
The opportunites for promotion, the benefits, the travel, a chance to live in other countries or just move around the States are all great reasons to join the Air Force. Your level of advancement is completely up to you, you control how quickly you make rank, whether it's the first try or the 10th, it's up to you. Furthermore, the Air Force instills many of the skills and abilities that civilian companies look for when hiring. Not to mention the opportunity to learn a career. If you don't like the first career under most circumstances you can "crosstrain" to learn a new career. And you can stay in for 4, 6, 20 or more years, again, it's up to you.
Cons
Sometimes you will find yourself stationed in a place that doesn't suit you, this is a temporary situation 99% of the time. Each assignment overseas has a return date programmed in, this date can usually be extended and under very rare circumstances be cut short. Stateside assignments do not have a must move by date but by volunteering to move other places you will eventually move to a new location. There are times when you have a supervisor that you don't get a long with. Much like the location situation, people come and go, either moving to a new base or a new job at the same base. If you get a job that you don't like, under most circumstances you can cross train and get a different job. Unfortunately there are times that leadership, while good intentioned, don't make the best decisions. Or seemingly make bad decisions but we don't know all the information. This is the biggest problem I see with the Air Force today. The "big picture" is not communicated down to the lowest levels where it is needed. We ask todays Air Force to do significantly more with less. Junior Enlisted are leaders before they are taught what is expected of them or even how to act as a leader. This also applies to Junior NCO's and even Senior NCO's. This is something the Air Force needs to change.