Originally Posted by
AnttiV
Yes, SK would earn more miles but it does not serve BKK and generally their presence in Asia is very limited. TK serves both BKK and HEL, has 2 year status validity and offers upgrade vouchers to their top tiers while SK offers status gifting which I do not require as I travel with my wife so we both have the same statuses.
The airline you fly and the airline ffp you credit flights to does not need to be the same. That is what alliances are about.
But generally better to be a ffp member of the airline you fly most and/or an airline of where live, due to ease of earning non flying ff miles/points.