Originally Posted by
powerful pete
Apologies, fair enough, I should have provided more information.
He is based in Lima, Peru. For travel to Europe he usually travels KLM metal, given that it is the best connection for us. He is an American so he regularly travels to the US for business and family visits, and in that case tries to fly Delta.
His question is really about whether there are major differences transferring his Delta Skymiles account from US-based to Peru-based.
In that case, SkyMiles would probably be the best choice. Assuming that he requalifies for Diamond, those GUCs are extremely valuable, and there is no similar offering with Flying Blue. SkyTeam has a better presence in LIM than the other alliances for TATL flights. BA is just now adding a flight to LGW, and Star Alliance doesn't having anything to their European hubs.