it's really not about one outperforming the other, it's about accepting the guitar's inherent feature & going with the one you prefer.
the GSA model, if you've tried one, has a more rounder, fatter neck. the SA160 on the other hand, has a slimmer, flatter neck, very similar to the RG's Wizard profile.
i urge anyone planning to buy either model to pick them up & play. many are of the opinion that flatter, thinner neck are faster but that's not true...
the SA160 is hung up together with the rest of the Ibanez models at the corner display wall, towards the Artcore models NOT with the G-sereis Ibanez