I would say that OZ F is more of an experience, if that's what you're looking for. You get the massive F suite with closing door, and I believe they still do the caviar service. BR is a fantastic business class, but it's still business class. Service on both airlines is excellent; but with OZ F, you will get slightly more personalized attention.

While ICN ground services are nothing like TG at BKK or LH at FRA, you will get F lounge access and an escort to the gate for your departing flight. The TPE lounges I find underwhelming. At least OZ F lounge is large, quiet, and well air conditioned - Infinity lounge TPE is none of those.

If champagne is important to you, you might ask on the OZ forum what the current situation is . . . there was a period where pax were complaining about not enough bottles boarded.