Are there any differences in taxes between Business Class and First Class when booking Qantas OneWorld RTW itinerary?

Hi Community, I have 423k QFF points and I am looking to book a RTW. I want to know if the taxes and fees are different for First vs Business Class? I could get a new credit card to get the points above 455k which I believe is First Class RTW. But if the taxes/surcharges/fuel cost a lot more flying first vs business then maybe I wont bother.

Is there benefits on doing business over first or vice versa. Both will be AMAZING, If anyone has any estimates of taxes for either options on RTW they have booked would love to get an idea as I am keen to start researching/planning. I know this will vary depending on where travelling around, but an rough idea would help.

In theory, the taxes of business class redemptions vs first class redemptions should generally be the same.

Hence, one train of thought is, if you had an abundance of points, it makes sense to go for first class redemptions since you are paying the same cash component.

Some programs like Velocity apply a surcharge on partner airline redemptions that is based on the cabin class. I don’t think this applies for Qantas redemptions.

You could in theory make a first class Oneworld reward booking but in reality there isn’t enough first class Oneworld flights let alone reward availability for you to be able to put together a RTW.