This post is for the benefit of anyone new in this area, and I welcome anyone to add to this thread with experiences with any providers.
Since living out here for numerous years, I started out with Sprint. Lets just say, it got to the point that every other call dropped and on many occasions it took several attempts to make a call. In addition, there were numerous occassions when I'd receive a call, but the phone would never ring (went to voice mail). Since then, I switched to T-Mobile and have no complaints. In addition, Sprint has many areas out here where there are dead spots on some of the local roads.
So, here it is, for this area, from experience:
Sprint - Service is poor and unreliable
T-Mobile - Service is good and reliable