In the past, AT&T's GSM model has been the phone to have when traveling overseas (especially Europe) since you can just pop in a local SIM. But according to this chart, it looks like Verizon might be better suited. The LTE bands 1, 3, and 5 are listed for both Verizon and Europe, but AT&T's 4 and 17 aren't found anywhere else. Does this mean I'll have better luck using the Verizon model with European SIMs (assuming I can unlock it and find nano SIMs)? Also, if I get Verizon's model, will I still be able to connect to 3G GSM networks, or am I stuck with CDMA wherever LTE coverage isn't available?