Well Visa dont give charge back that easy. I did subscribe to a model data base
http://www.onemodelplace.com
They dont have a way to cancel auto-rebill so after I sign up I follow their rules and send a e-mail asking to have my auto rebill cancel. They reply that it would be done. 3 week later they still didnt cancel it so I send a other e-mail telling them that if they dont cancel my auto rebill I gonna have to charge back them. They ignore it.
So I call visa for a charge back and they asked me to send all the e-mail as a proof I did write to them and asked twice or they wouldnt charge them back.
So at least they ask for some proof and dont make it a easy process. it take me 45 min on the phone if I include the waiting time.