Switching from a V3x on 3 to another phone

[sanofi]

I have a v3x atm and wondered if I had an unlocked phone would I simply be able to put my sim in it and use it as normal? Considering that the v3x is a 3g phone?

 

[jhmaeng]

For starters, your new phone would have to be 3G as well (as in, not necessarily provided by the network "3", but capable of W-CDMA 2100Mhz band, such as the SE K800i or Nokia N-series).

I can't recall exactly whether "3" frowned on people using non-3 supplied WCDMA phones (I'm guessing probably not, since it doesn't incur any extra costs to them), but expect a nasty letter pretty sharpish if you used a non-3G phone with your 3 SIM card.