It will all depend on why they have given you the 9720.
If connected to the corporate network through BES for a reason (either internal system access, or security), I don't think they will be happy for you to put their sim into a non-secure handset.
Both the Z30 and iPhone will have different size sims.
They also have data allowance diffrerences... where a BES enabled old style blackberry could work fine on 500mb, both phones you mention would require 1gb+ to cover the same usage.
If the company are happy for you to put the sim in your own handset, then you are best to let them know so they can change the price plan accordingly, and also issue you the correct size sim to use.
