I have the Verizon service with a Sprint card as back up and rarely have a change to use the Sprint card as the Verizon always works. I didn't even bring the Sprint card with me on the trip we are on now. The only place nothing seemed to work (not Nextel, Sprint, Verizon or any of it hardly) was the Grand Canyon. My Verizon card worked at the White Sands missle range where they tested the first Atom Bomb about a week before showing it off the rest of the world. Talk about the middle of nowhere. I've had very very few places I couldn't connect and I'll say the same about Verizon cell phone service.