Originally Posted by SkuzFoz
The US version just has some extra frequency bands for T-Mobile. They mostly operate on a different band in the US than they do in other countries. If you're not using US T-Mobile, there's really no reason to buy the US version. The Global version will work a little more reliably for you.
The global version will likely work a *lot* more reliably for you if you're outside the United States. The U.S. version doesn't add extra frequencies, it trades those frequencies for other frequencies. So the U.S. version cannot work on certain frequencies that the global version can, and vice-versa. (The U.S. version cannot do HSPA on 900MHz while the global one can, and the U.S. version doesn't support networks that use 2100MHz for the downlink and 1900 for the uplink...its 2100MHz support is limited to AWS downlink.) This means that the U.S. version will, in a large percentage of countries, be limited to using EDGE networks. It really is too bad that Motorola couldn't manage to make a single model that covers all of these bands...
My impression is that there are very few carriers worldwide that operate on band 4/AWS-1. T-Mobile U.S. is probably the largest one, and even they are actually in the process of refarming their spectrum. My understanding is that they are turning down some 850MHz 2G transmitters, moving some HSPA+ over to that spectrum and some to 1900/2100 (band 1), and then re-using their AWS-1 spectrum for LTE. Once that happens, even the global version of the Moto G will work fine on T-Mobile. The global version already works on AT&T, and if you are in a metro area where T-Mobile has already completed the spectrum shuffle, the global version will work for you, too (and allow you to use your phone on HSPA networks if you ever travel outside of the country!). So for many people in the U.S., I would argue that the global version might actually make more sense, especially looking forward.