I am looking to buy a used 5s from USA and I can see two models there A1530 and A1533. A1533 is CDMA but from what I read its dual band and it supports GSM too, so I am a bit confused. Would anyone please clear if it will work with GSM service provider in India like BSNL? I am looking at this model as its a fair bit cheaper than the other one. Please help. Thanks for taking time out to read this. Regards.