i actually tried replacing feral bonds with SoG and it didn't differ. you just seem to have less elemental master wins with SoG. so i can tell you to keep the feral bonds.
one other thing.. you don't easily deck out with this deck, so keeping eternity felt pointless. thus i removed eternity and added two quints and SoD. i get better win percentages this way.
I'm a bit surprised that an SoG vs. Feral Bonds makes no difference... 2 SoG's results in 10 life per turn, regardless of creatures out... so if you're stalling for key combination of cards (quint + oty, etc.) any damage you're taking will be reduced thanks to the SoGs.
With Feral Bonds, you need 5 creatures out to equal the healing you get from 1 SoG... I can see that in the late game, the Feral Bonds will help you establish EM, and be far more beneficial, but that's assuming you get to the late game phase and can stop any initial rush the FG's throw at you. And by then, you should already have control of the board and no longer struggling...
SoG's are also MUCH cheaper to cast (2 random quanta), and could be cast much earlier to help eliminate any early round damage you're taking, while Feral Bonds (upped) cost 4 green quanta + the cost of casting creatures in order to utilize the bonds. And the cheapest creature costs to build 5 creatures are:
Queen + 4 Fireflies is 15 quanta + 4 = 19 quanta
Oty+ 4 tasty enemies = 9 quanta + 4 = 13 quanta
The only thing I haven't considered is whether the 6 sundials and 2 antimatter create enough stall for the SoG's really not to matter?
Just some thoughts...