In the DFW area. I had my dad's 05 Avalanche for a few months last year after he passed away and the reception was practically non-existant. Having no signal and no AUX or bluetooth options for devices was a beating (first world problems, I know.) My wife's 14 Traverse picks all the stations up in clear HD and never waivers from it. My 14 Silverado (LTZ but no nav) seems to struggle quite a bit. Not as bad as the Avalanche, but nowhere near as good as the Traverse. It seems like it's just dependent on which direction, and how strongly, the wind is blowing as to whether or not I'll get decent reception.
I've also noticed, when comparing the two 2014 vehicles, that hers will immediately start playing a station in HD when its tuned to it. Mine, on the other hand, seems to grab the analog signal first and then gropes around a bit for the HD one before switching over. On the HD only stations, they just take anywhere from 3-8 seconds to start playing when I tune to them. In the Traverse, all the stations "just work" and they just work instantly.