Both Verizon and Tmobile have worked great at Bonneville. NO COMPLAINTS... Only complaint I have is not much service by the way of Wyoming going thru,,, but do you blame them for not wanting to put towers in Wyoming...
As for the cell phone roaming charge on verizon, turn the phone off and back on and it will locate new towers and not charge roaming. There is a couple key strokes to do this also I just cant remember at this time.
Jon