Originally Posted by dukerau

Yes, you can book in different classes each way. But United decides which cities are your destination and stopover, so if it's pricing out wrong it may be because you aren't agreeing with United on which is which (and you lose that battle ). For example, if you want to go to New Zealand and Australia and you fly SFO-SYD in business, stopover, SYD-AKL in business, destination, AKL-SFO in economy; United may consider SYD to be your destination and AKL as your stopover and price you at business both ways. So you'd need to change SYD-AKL to economy to price as you want.

Can't stop in Europe en route to Australia.

Generally you don't have the luxury of selecting the airline you want unless you are very flexible on days. Given the choice I would go with EVA, ANA, or Singapore. Asiana is fine but much more travel time. But if you're paying more for a partner and that's what's making you do economy on the other direction, I'd rather do United business both ways than a partner business one way + economy the other.

Originally Posted by LondonElite

Agree with all that, and I would emphasise that, with possibly one or two exceptions worldwide, any business seat > any economy seat.