Good point. My area works flawlessly for almost any carrier. The DFW metroplex is a hotbed for delivering the highest possible technology not only for cellular but also other things like internet and HDTV. The problems arise when you venture out into the wild, wild west of the massiveness that is the state of TX and rely on Google Nav/Maps to get you there and trying to get a phone or internet connection out in the hinterlands.
The unlimited data is only one reason I'm clinging to Verizon even as they pry every last dollar they can from my wallet. I've made it a personal mission to explore all of TX and, so far, have been gobsmacked to find myself in places so remote the locals have to take a bus to town to hunt and yet I can still use CGeo on Verizon to find a geo-cache! Of course this means I want the phone with the best 3G/LTE/wifi radios and they don't have a problem with switching between them.
Just a quick edit, I currently have the much maligned HTC Thunderbolt and, in the beginning, the radios sucked. Then we got updates, way too long IMHO, that made the reception much better. The recent ICS update has made radio reception better still but at the expense of other functions. The hardware just isn't up to the task of the new OS as far as I'm concerned. Having said that, based on the new phones available on Verizon, I'm still in no hurry to switch no matter how slow or outdated the TBolt may be.