I live in the USA and I bought the Xperia Z from T-Mobile a while ago. I do know that I have the C6606 variant, and it is only set to support LTE Band !V (1700 MHz). I was just wondering if all the variants of the Z have the same baseband chips because if so, I was thinking of flashing a firmware baseband from the C6603 so I can get more LTE bands for when I go to the Philippines in a couple of months. The carriers over there supports Band I (Smart Comm.) and Band III (Globe Telecom).. I will be staying there for a while so I would like to get the most out of my phone, so help please?