Look into the GT front bar while you're at it. Small differences in diameter are actually fairly large differences in stiffness, so don't feel "cheated" if the GT bar is only a couple of mm larger in diameter. The bottom line is that you really want to keep the front and rear suspension stiffnesses somewhat proportional (IOW, don't just stiffen one end of the car).
Decided on the Hellwig sway bars, going to call closer to christmas and order them, so by the time we arrive home, they will be ready to install. (i cant wrap boxes to save my soul, so an IOU will be in order)