Not that we need any more, but a JPY data point. Purchases were made 20 minutes apart.
A pizza purchased with CSP (Visa), JPY 1868 = USD 17.56 (1 USD = 106.38 JPY)
A couple electronic items purchased with a First Tech Mastercard, JPY 1836 = USD 17.09 (1 USD = 107.43 JPY)
Unsurprisingly, the rate is off by almost exactly 1%. I didn't realize that "no foreign transaction fee" actually meant "we'll still get 1% by manipulating the exchange rate".
Most of my purchases while travelling are categories that get double UR points, so I'll probably suck it up and effectively pay 0.5¢ per point for them.