Here are some numbers to compare for those who are curious.
Google Docs Clicky
Enemy INT ranging from 1 to 200 INT then averaging those out. Numbers are assuming Taru 99BLM/RDM with no INT merits (forgot about those...) using this set (minus the legs of course):
Sorc.+2 does win out on higher INT mobs but only barely. However, NQ/+1 still wins over +2 on correct day. Personally, I'm going to stick with my NQ and my Goetia +2 since the damage difference between Goetia and Sorc. +2's are so small.
No gear set for this, but using +32 MAB from gear, if you're nuking something with INT ranging from 76-80, Goetia+2 and Sorc.+2 are equal. Above that range, Sorc.+2 wins out by a very small margin, below, Goetia+2 wins by a small margin.
A big question to whether or not to +2 this is if you are able to have both the NQ/+1 and the +2 at the same time.
If you can have both, and if you are obsessed with OMGWTFEPEEN damage, then get NQ/+1 and +2 both. If you're not too worried about a 6 damage average increase (or if you can't have both), then stick with Goetia+2 and NQ/+1.