Sprint has been my phone provider for eight years and I have not had any major problems with signal until now. I used to live in San Diego, CA and now I live in Santa Cruz, CA. When living in San Diego I had no problem using my phone. I got service just about everywhere except in the boonies in the far east counties which is expected. Also, when I traveled to L.A., San Francisco, San Jose, and Las Vegas, the service was perfect.
The only time I am having problems with service is when I moved to Santa Cruz. In Santa Cruz there are many dead spots with phone reception. The sprint map shows that the city is covered but do not believe in the hype. I am not bashing sprint, but Santa Cruz is such an odd city that everything is out of wack. Just look up Mystery Spot and you will know what I mean. But all jokes aside, major areas in Santa Cruz that did not get reception were at UC Santa Cruz and Western dr. Not ever Verizon got service on Western DR. Other than that I can get good service in other parts of town.
Overall sprint service and reception is really good, even when roaming to verizon towers. I think it is just the small cities and rural areas where it may suffer.