Q: I want to buy an unlocked 4s from apple and use it permanently on a foreign CDMA cell service (IUSA Cell in Mexico).  I am getting conflicting information.  Thoughts?

I want to buy an unlocked 4s from apple and use it permanently on a foreign CDMA cell service (IUSA Cell in Mexico).  I am getting conflicting information on whether this is possible.  Apple website says the phones are unlocked for GSM use only. 

I called apple when i bought an Ipad to help decide on a GSM vs CDMA version and was told that if I went to Mexico with a CDMA version of the Ipad (2) that i would call the carrier give them some numbers and they would activate it.  When i returned I was to call Verizon and reactivate it in the US.  I ultimately got the GSM version so i never tested the theory. 

I am now thinking of getting the 4S to use in Mexico permanently but want to use it on a CDMA carrier because it is half the cost per month.  But will this work?  Thoughts?