Sprint and T-Mobile both use the same frequency so the signal propagation should be the same. It all depends on a number of factors such as how high the panels are aimed and how high the power is turned up. Many sites operate at less than full power and are aimed with a downward tilt so that pilot pollution is kept to a minimum.
If they live in Iowa that was Nextel Partners. Now don't let Nokia and other international providers hear that. They might change there minds about CDMA being the future :lol: