I'm planning a RTW in June, half business / half pleasure. I could put the itenerary together just using BA & QF. Is there an advantage to using an OW RTW ticket given the following path. Or is there a BA/QF RTW fare available that follows this itenerary?

ZRH-LHR-NRT (BA)

NRT-Cairns AUS (QF)
Cairns-Brisbane-AUK (QF)
AUK-Buenos Aires (QF)

and one of the following closing routes...

- Buenos Aires-London (LHR or LGW- don't know) - LHR-ZRH (on BA)

or

- Buenos Aires-Madrid-ZRH (on Iberia)

All travel is in Business Class

The other option is to come back via the USA, which would be easy with BA, but I'd rather avoid the travel crunch in the US during the 4th of July if possible.

Thanks, Jenn