The following is my experience on T3. Do not leave...

The following is my experience on T3. Do not leave your gifts shopping till the last minute in the airport. There just a couple of shops in the airport and they are much pricier then in Havana, (including postcards, cigars and rum). Plus, the selection of stuff you can buy is quite poor. For example I was hoping to buy Cuban coffee beans, but there was none. General perception communicating with shops cashiers: they hate you. Customs personnel is relatively friendly. You can send your postcards from the terminal (Update: postcards arrived 3 months later).