I installed a cold weather variant a couple years ago, it blasted out heat during the -5 degree cold snaps of last winter, maintained its full capacity, and did it surprisingly efficiently. But probably not worth it to go cold climate in Austin :-)
Which system did you install? Who installed? DIY or a contractor?
DIY, Midea 18k BTU, Hyper -22°F, 23.5 SEER2, 15.5 HSPF. Its air exchanger outside is a good bit bigger than other 18ks, I suspect that's part of how they hit the amazing efficiency at low temps.