I would say this is more like a bank than a wallet because it enables the user to have an essentially limitless number of accounts with different security attributes. Additionally, it provides the user the ability to create permissions and pairings so they can make automatic payments and make payments using any paired device like a laptop or smart phone. This means that is really a hub of commerce as well a a mechanism by which to create cold storage on SafeCards. That being said, the planned MSRP for the device will be ~$300. More coins such as BCH will be added overtime.
It says the smart cards generate private keys based on data that was programmed into them at the factory:
>Physically uncloneable functions (PUFs) convert each chip’s unique electrical fingerprint into digital entropy that cannot be stolen or observed.
So that means you have a copy of the private keys doesn't it? The trezor OTOH gets entropy from the PC.
No one, not even you, has the private key. The key is only manifested physically. PUFs are like electronic snowflakes.
They are made through uncontrollable randomness in the manufacturing process. They cannot be observed or reproduced and each one is unique. The entropy in a PUF is used to create a signature, but the private key is never actually knowable outside of the device. This is the most secure way to store a secret because even nation states are not able to derive a private key from a PUF on a secure microcontroller. For anyone familiar with nuances of security a PUF is the best way to keep a secret.
That being said, if a customer does not want to use the PUF, they can store a secret on a smart card that is generated from a BIP39 process similar to trezor. This is less secure from a physical standpoint because an electron microscope could be used to read the secret from the microprocessor, just like it could be read off the trezor.
Additionally, it means that a plaintext copy of the seed likely exists somewhere written on a piece of paper, which not only suffers from durability issues but can also be easily compromised.
In terms of backups, hierarchical multi-signature systems would be they way to "backup" PUF based accounts, because the cards themselves are "physically unclonable" so they cannot be individually backed up because they are impossible to read or reproduce.
> a PUF is the best way to keep a secret
I'd say this is pretty close to my personal view and the opinion of other hardware security people I'm interacting with - http://www.securitydocumentworld.com/article-details/i/11275/
Can you be more specific about the PUF you're using ?
Let me know if you have any questions. One other thing that may be of interest is that in a multi-sig wallet multiple entropy sources could be used for the different keys. One could be a PUF, the other could be a BIP39 generated on the Lattice1 or elsewhere, and the 3rd could be a backup provider like BitGo. Then the user is really mitigating their risk of flaws in any single tech implementation.