We are thinking of getting a Treo 650, to use with T-Mobile. Some questions: - I have seen references, on its product diagram, to SIM cards. The diagram is labeled "GSM only." Therefore, when buying a 650, must we specify that -- we want "GSM version" (?vs. CDMA version?) -- we want the Treo to be unlocked - Does the Treo 650 allow for the viewing and editing of Microsoft Office files, or either but not both, or merely for the ability to download and store? Is it a function of the Treo 650 itself, or Palm OS? Thanks.