I'm taking my first trip to Japan (and Asia as a whole) next week, and I would love the board's help with a question.

Since I put most of my purchases on Amex here in the states (and my Visa is from Bank of America), I applied for a new Visa from Capital One to cut the fees that I would pay while overseas.

Being brilliant, they sent me a MasterCard instead of a visa (still forex-fee free). Before I call them up and try to get an expedited visa sent to me, what is MasterCard acceptance like in Japan compared to Visa? Are they about the same? Is one more widely accepted than the other?

Thanks a bunch.