Also there is an option to set preferred network type by dialing *#*#4636#*#* and then tap Device information, scroll down and there is a selection box to make ur choice.
Not sure how to make the set choice stick though. It changes, after reboot or if u back out of the Device info, back to GSM/CDMA auto (PRL).
?? Don't know much about this...may be sim dependant as to what will stick. :/
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