I did my PPL with OBA and never got the impression that I was being trained to fly only in the United States, even though it was a JAA-PPL training. I hold a UK license, live in Germany, and have flown in several European countries without noticing a big difference. If you understand the rules and regulations of the respective country you are fying in, and have studied the appropriate charts, you won't have any problem flying in any part of this world.
WP