FV does not provide digital money. But it was the first Internet payment method. The problem with this scheme is clearly the lack of encryption methods. Internet E-mail is not safe at all and easy to forge. Building a payment system on such a weak basis without any cryptographic methods does not inspire confidence. Because most of the people do not know about cryptography, they can only believe FV's PR, which broadcasts the high security message. FV is also not anonymous at all. The scheme is built on the traditional credit card model, which makes every transaction traceable. Moreover, the messages are not encrypted and are vulnerable against a network eavesdropper.
There is one more big problem with the FV scheme: the buyer first receives the goods and then decides whether s/he wants to pay for them or not. In many cases, we can imagine that the buyer is not completely satisfied with the goods received, and will therefore not be willing to pay the entire sum. These kind of problems are usually very difficult so solve and require human interaction.