Answer:
This is a personal decision based on what you hope to do and hope to gain from the experience. While the Army can mean you may see more places, the Air Force usually assigns service members to installations for longer durations. This can provide stability if you have a family with you. Many Army MOS's translate very closely to civilian jobs, but most Air Force jobs are directly related to those in the civilian work force.
Both will teach you discipline. Both will give you opportunity to learn.