I'm a big fan of OZ F on the A380, but it's a really long detour. If you'd do something constructive with the time then go for it.
I've been pretty disappointed with the food on TG though the service is usually quite good. OZ food though has been consistently good on the routes I've flown with them. Entertainment seems much better on TG where OZ is a bit lacking in a wide variety of Hollywood content. Also, OZ F lounge in ICN is incredibly disappointing, so if you don't have work to catch up on then a quick dash outside the airport may be something to consider.