Mobile phone/data performance is very location dependent. For the majority of people, one is significantly better than the others where they live for largely historical reasons. If I lived 50 miles east of where I do, I might prefer VZW. If I lived in DC, I might prefer T-Mobile. There is even someone here on SatelliteGuys (can't recall who), who thinks that Sprint is the best, and it probably is where they live. Overall, the top two are going to provide the best coverage nationwide, and T-Mobile is coming on strong in coverage. Verizon has great coverage where I live, but it often unusable due to how oversold the network is around here. I tried switching to VZW in December and had to switch back to AT&T, just to get decent performance. As mentioned previously, 50 miles east of me, Verizon is the bomb. On average, if you can get coverage, Verizon is going to be a little better than the others, but not always or everywhere. This is why people I know who travel a lot often prefer Verizon, even if it sucks where they live.