Purchased two different local SIM cards for my iPhone while in Lisbon meo & vodaphone. Can only text locally but not to the US, and can receive email but not send to the US. Before I left I called my isp to insure my email would not be blocked. The second phone (Samsung) does not recognize either sim. It is a pita to not have this working. Should have switched to a global plan before I left.
As a plus, google maps seems to work fine even with the US sims (no global plan). Back to the phone store today.