So it's finally out

I was waiting for it, and i'm happy that my boy Corrin received his deserved refine to his weapon. Now here's the thing: looking at his IVs (+Atk -Res) and the fact that he's on my mergin project (waiting for so many Corrins to be summoned) and him being S supported with a +Def -HP Azura i wanted to know: should i go for the refined effect, or maybe go for the Atk/Spd Refine?