Today, I just paid a hotel in Japan with it, and it is pending on my statement at 110.3 JPY to the USD, when the spot rate is 115.
Pending doesn't mean squat. It will often change when it posts. With that said, going through this thread, Visa seems to be the worst when compared to Mastercard and Amex. Even knowing that, I use the CSR for the 3x categories lately on international charges (figure I end up getting 2x UR points with the approx. 1% currency surcharge they seem to add on). If your sensitive to poor currency exchange rates I would stick with Mastercard or Amex. I like to mix em up to whichever fits my needs.
About DCC. That's a separate issue. I've only had it happen to me once, in South Korea and I went back to the lobby and corrected the issue. It sucks that it happens, but you have to be vigilant and make sure charge is in local currency when you get the bill (especially if it's your first time staying at the hotel).