OMT - in my experience, having just a single hardware token (for a password, passkey, 2FA, or whatever) is dangerous, as it’s too easy to lose it or get it wet, so I tend to keep two: one on my keychain, one at the house. I’m not sure how well this kind of device would work in tandem with another just like it, especially at $100 a pop (and coupled with my previously mentioned concerns about crowdfunding hardware).