Speed isn't everything when it comes to wireless service,\u00a0but it sure comes in handy when you need to upload a large video or stream a new album. That's why the major carriers constantly boast that they have the fastest networks. They all can't be number one in speed, of course, but the four leading wireless providers are delivering faster speeds, in more areas, than ever before \u2014\u00a0and even Sprint,\u00a0a perennial slowpoke, is finally making significant gains\nThe latest indication of improvement comes courtesy of PC Magazine, which conducts extensive wireless testing in 30 U.S. cities. The online magazine says that "for the second year in a row, Verizon Wireless takes the crown as America's fastest mobile network by delivering the quickest speeds and the best coverage across the map."\nAT&T did almost as well across the country, while T-Mobile is strongest in the West, according to PC Mag. Sprint is the fastest in only one city \u2014\u00a0Denver \u2014\u00a0but the carrier's average speed doubled, and even tripled, in many cities compared to last year.\nHowever, Sprint is still significantly slower than its rivals. Nationally, Verizon's average download speed is 19.1 Mbps; T-Mobile and AT&T are virtually tied at 15.3 Mbps and 15 Mbps respectively, while Sprint clocked at 12.7 Mbps. Although T-Mobile's national average download speed is slightly higher than AT&T's, the number is misleading because AT&T is faster in many more markets.\nWireless speeds vary greatly from city to city, and even from neighborhood to neighborhood. Average speeds don't tell you much about the reception you get in your home or workplace, so it's always best to try out a service before you commit to using it.\nFor example, Verizon's average download speed in San Francisco is 18.3 Mpbs, according to PC Mag, but when I measured the speed of my Verizon iPhone 6 in my home it was considerably slower\u2014\u00a0just 11.05 Mbps downstream and a very pokey 0.22 Mbps up.\nOverall reliability and the quality of voice calls are also important considerations. PC Magazine didn't measure these factors, but RootMetrics did earlier this year.\u00a0The company\u00a0looked at five different categories (reliability, speed, data, call performance, and text performance) and then crunched the numbers to derive weighted, composite scores.\u00a0Reliability, a key metric, refers to the overall performance of the networks, and it factors in accessibility, dropped calls and more.\nVerizon was the big winner, and it\u00a0came out on top in four of the five components that contribute to the overall score; AT&T edged out Verizon in text performance. Sprint was the loser, and it ranked last in speed, data, and call performance.