Ok, just found out. Just need to press triangle to open the info box for the item.
When i toggle on the info for a blitz bolt scroll, i can see the air damage it will do.
On my mage, aerotheurge 2, intelligence 11 it says: 57-63 air damage
On my roge, aerotheurge 0, intelligence 5 it says: 54-60 air damage
The bonus from the mage seems quite disappointing to me.
