I think it's comparable to more "traditional" hardware wallets: the chip we use is very similar to the one used by Trezor, so we have a very similar security model.

On top of that our device doesn't have a battery so it's completely offline when not in use. And we use NFC, which is a very simple stack with pretty low attack surface, so compared to other mobile-compatible devices based on Bluetooth we should have a security advantage, at least on paper.