blockchain.info is great compared to some black box wallet but their model can't provide per transaction two factor, meaning once malware has your keys in memor

blockchain.info is great compared to some black box wallet but their model can't provide per transaction two factor, meaning once malware has your keys in memory you are good to go and you are going to have a real bad time. That's possible with multisig and GreenAddress offers 4 different kind of 2FA: Google Auth, SMS, email and Phone (robot call)