Last year I booked a Business Class ticket SFO-SEL-SYD using Delta miles, with a stopover in SEL on the return. On both return segments SYD-SEL and SEL-SFO the agents bumped me up to FC. I wanted to tell them I already was flying on a free ticket. Carriers such as SQ, CF, and ANA often get the well-deserved accolade, but KA service was very good...probably because it's in heavy competition with Asiana.