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Independent mobile network tester RootMetrics has completed its latest round of nationwide speed and reliability tests, and while the best overall performance award goes to Verizon, the speed prize that most tech geeks really care about was a bit of toss-up. Both Verizon and T-Mobile posted impressive 4G bandwidth numbers, reflecting big upgrades both made to their LTE networks in the last year.

Seattle-based Root no longer compiles an average speed number for a carrier’s entire coverage footprint, which is frankly a rather useless number for gauging overall network performance. Instead, it’s now showing the number of metro markets where a carrier’s average download speed hits a particular benchmark, such as 10 Mbps or 20 Mbps. (You can find Root’s individual city reports here.)

Root found that in the last half of 2014 [company]Verizon[/company] averaged a 10 Mbps or better downlink connection in 122 cities, while [company]T-Mobile[/company] did the same in 96 cities (that’s out of a total of 125 markets). [company]AT&T[/company] wasn’t far behind with 93 cities pumping out 10 Mbps-plus speeds, but when you start moving the bar upwards, T-Mobile and Verizon really shine. In 41 cities, T-Mobile averaged 20 Mbps of faster speeds, while Verizon was producing similar fast connections in 40 markets. AT&T hit that benchmark in only 14 cities.

At this time last year, AT&T held Root’s speed crown, but a lot can happen in a year. Verizon and T-Mobile have been tinkering a lot with their networks. Verizon turned on a brand-spanking-new LTE grid in the Advanced Wireless Services (AWS) band — what Big Red calls its XLTE network — doubling the speed and capacity of its original 4G service. Meanwhile T-Mobile has been playing musical chairs with its existing spectrum and airwaves its gotten through acquisition, producing 4G networks in many major markets that match Verizon’s megahertz for megahertz.

AT&T is upgrading its networks as well, but it’s being a bit more methodical, tapping into LTE-Advanced technologies to add capacity here and there. Consequently we’re not seeing a big jump in speeds from AT&T, but a gradual improvement across its 4G footprint. For instance, in the first half of 2014, Root found AT&T could boast an average of 20 Mbps in a single city. Six months later, that number was up to 15 markets.

Root also found AT&T to have the far more reliable network with far fewer instances of call drops, call failures and lost data sessions than Sprint and T-Mobile. Ma Bell fell just Verizon in the overall RootScore rankings.

And where does [company]Sprint[/company] fit into all this? The answer is just barely. Root ranked Sprint No. 3 ahead of T-Mobile in overall RootScore, but despite all of Sprint’s talk about producing a barn-door-busting LTE network, its 4G service is still years behind the competition. The large majority of Sprint cities tested were averaging download speeds below 6 Mbps, and not a single market hit the 20 Mbps benchmark. One day Sprint’s Spark may truly become the mother of all networks, but that day is certainly not today.

This post was updated on Wednesday to correct the number of markets in which T-Mobile achieved 10 Mbps or better average speeds from 108 to 96. The original figures Root supplied to Gigaom had an error, which the company has since corrected, but the change does not affect any of the other numbers or conclusions in the post.