Thanks.
1. Does BB service (BBM, email) work off WiFi as well, just OTA?
2. What about if I use local SIM? Obviously it will not have BB service, but do I still have to be worried about shutting 'Data Services' OFF, or 'Data Services' will not be working anyways?
1: Yes, those services will work over wifi. You can test this out at home by turning off your data connection and running the device solely on wifi.
2: You will need to have data services on in order to use data on the local carriers network. If you have a local sim card in your phone, you won't have to worry about roaming charges. But as you already stated, you won't be able to get pre-paid Blackberry data in the country you are visiting. A regular (non-Blackberry) data plan won't do you much good, so I wouldn't bother.
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