Does the current the GT beat the SS? The SS has a few more HP but the GT is smaller and lighter.
Depends on what aspect you're looking at. If you're talking acceleration, then the GT. But if you're talking ride and handling, the SS probably just a bit better due to a more sophisticated suspension.
With IRS and comparable power to the current model, the 2015 should dominate the current SS in every category. Then we'll have to wait to see how Chevy counters with the 2016 Camaro.