Three of us at work all have iPhone 5S's. One on Verizon, one on Sprint, and I'm on AT&T. Our office is in Kakaako. The Sprint guy rarely gets more than two bars, and usually does not get any coverage at our office. Verizon & AT&T iPhones have full bars in the same spot. For the Sprint guy, text messages usually go through, but he is unable to use data consistently. He'll be switching to T-Mo next month when his contract is up because he has coverage problems elsewhere (not just at work). Verizon guy is on Verizon because he's originally from Hilo where Verizon has good coverage. He has no problems here on Oahu too. I have no major coverage problems with AT&T, except at Aloha Stadium. I stick with AT&T because I have a grandfathered unlimited data plan for the iPhone. I would leave for a different carrier if AT&T ever eliminates my plan out of principle, but don't have any major issues with them.