They've been suggesting that they use a unified network on their commercials when they try to suggest that the merger has made their network broader.
Anyway, I use Sprint and I've had pretty decent coverage at WDW. A while ago I had some issues where the network seemed congested, I was having difficulty getting any calls out although I definitely had a signal. But in the past year or so it hasn't been a problem.
For random trivia purposes I heard that they'll even have a way to use Sprint (and some other providers, I don't remember the rest) cell service on their cruise ships! Of course there'll probably be an astronomic surcharge associated with the service, but.. I'm just intrigued about it. That probably means they'll have a satellite connection to the cell providers, so you'll get an added satellite lag to the usual cell encoding lag (it's there, if you've ever called a land line phone with your cell phone and listened to both handsets at once you can hear a definite lag).
