Originally Posted by
corpgator
Funnily enough, I got offered DCC at a restaurant in Buenos Aires back in March, I jumped all over it since the rate was 1 higher (15 vs 16). At least I assume it was DCC. She asked if I wanted the charge in ARS at the day's rate or in dollars at 16. Knowing the day's rate was around 14.8, I took the 16, and I confirmed that's what I got when I looked up the transaction later. Maybe it was some other ploy to get dollars, though.
There are these isolated cases showing where DCC can be favorable to the cardholder.
Others that come to mind were non-CHF denominated cards used in Switzerland before the Franc appreciated and GBP denominated cards after the Brexit vote. Neither of these two situations could have been reliably predicted, of course. It's still best, as a general principle, to decline DCC when offered.