If those are the only two choices, I'd personally go with Super Flower made G3 series (I assume Super Flower still makes G2 and G3 units for them).
I don't think I've ever seen a review on the GA from any legitimate hardware review site. On paper it looks good, but without testing it's hard to say how good/mediocre/bad it is.
On a side note, EVGA has way too many different models (in the same performance/price categories), and I have no idea why they do that. After they moved away from using Super Flower for their performance models, they went absolutely crazy with numerous new model releases.