Coverage isn't a problem on any carriers (except T-Mobile) here in Baltimore. It's the quality of the coverage that matters here. Where TMo has coverage, it's pretty good, at least data wise. Voice isn't good, but that's expected of any GSM carrier. AT&T voice isn't great either, but they also have consistency problems for data. I would be getting 3mbps down one day, and .5mbps the next. Sprint, well you all know. Great voice, horrible data. Getting better now though. A lot better.