Vanya Gear Set...Not As Good As I thought?

[Pofo]

I just don't see how it's better. I'm trying to find a way to justify the purchase. you meld materia for side stats but it just doesn't seem to be better than DL for the cost even with the forbidden meld.

Vanya is and always will be superior to Darklight.

Darklight Robe of casting: VIT32 /INT33/ Accuracy43/ Spell Speed30
Vanya Robe of Casting (with the Proper meld): VIT+20/INT+20/Accuracy+27/Determination+13 --- Meld with Crit +27 / Determination +5 (Total 18 DET)
Vanya Hat of Casting (With the Proper Melds): VIT +12/INT+12/Crit +11/Determination+11 --- Meld with Accuracy +16 / Crit +5

Vanya Combo Totals: VIT+32/INT+32/Accuracy+43/Determination +29/Critical Hit Rate +43

For the loss of a single INT, you gain 29 Determination and 43 Critical Hit rate. That 29 DET far overpowers a single INT, let alone the crit rate is the main sell point alone even if it didn't have the Determination on it.