Root bark is generally considered higher in concentration of dmt. However, phyllodes are just the extension of the bark itself, they're not actually a leaf therefore are quite high yielding too. Phyllodes are far more sustainable so that would be my reccomendation due to sustainability. The yeild will not let you down and is generally fairly similar but lower.
Both are just as good for extraction, no changes need to be made between the two. You may get a little emulsion issues when working with acuminata but this is easily rectified. Acuminata can be a bit finicky to get a good yield but once you learn a few tricks with it, it's quite easy to get a good percentage.