Well it does vary from plane to plane, however the A6m really doesn't gain much in my opinion from advanced fuel management. 190's, P51's and some others have center of gravity issues with a full load of fuel. Giving you a big advantage to burning off the the Aux tank below 25% first.
As to the DT I've not seen any advantage to taking the wing tanks vs the center drop.
Mostly it would depend on what else I want to load. A6m has such great range that mostly you can load 50% or 75% fuel, no drop and go fly.