Ok, Thanks people for your help. With Kiwi Flyer's assistance last month, I had the following routing (for early April): JFK-SJU-LAX-SJO-LAX-SAL-LAX. This gives 15,082 mile and 540 QF SC's. On a pure MR basis I could go: JFK-SJU-LAX-SJO-LAX-SJO-LAX and get 15,888/580.

Wandering Fred's routing gives 520 SC's, but may not be available to me in the one itinerary due to seasonal scheduling.

PresRDC's examples are 13694/540, 12713/540 & 11187/500.

All have interesting destinations and any routing giving 500 SC's or more is quite good.

(I'm looking to maximise SC's, miles are not as important. The bands for D class with QF are 0-600:40, 601-1200:60, 1201-2400:80, 2401-3600:100 etc.)