Switching to Vodafone is likely to save you money! It will also allow you to reduce eliminate roaming charges if you switch to another mobile phone operator!
I had a sim of RIM which is 9 years old but I was completely disappointed with the service of RIM, then I choose Vodafone and request for MNP.
Now I am using vodafone network which is really brilliant and very vast.
Advantage of this network is it is be with you even you travel or at basement