As far as I can glean from my experience and searching the internet, it doesn’t matter which SIM card you use. It is the device that matters. I have a 3G phone (Nokia E71) and an older SIM card (I’m almost certain it is not 3G) and I have no problems making phone calls, surfing net, getting emails, etc from the 3G connection. I did read some people saying you need a 3G SIM to do simultaneous voice and data. As in talking on the phone and searching the internet. But I also saw others say they tried it and it worked fine with an older generation SIM. I also saw someone stating you needed the 3G card to do video calls (I haven’t tried doing a video call, so I can refute or verify). As far as I can tell now, the advantage of a 3G SIM is expanded storage capacity. I wish I could be more help. You could try talking to customer support (or multiple agents/store locations until you feel comfortable with an answer). Also, if you feel it might help and can get a new one for free you might as well try to do so.