Two Computers; One Account - How do I avoid locking myself out?

[Beckett]

All right. I'll give it a shot, though I do have this old-world mentality of trusting physical objects more than digital ones (and my ToR and Blizzard Authenticators have yet to fail me despite being quite old now), so I might pick up the physical one at a later time if the app fails.

I used to have the physical authenticator, but switched to the app when they released it. I've never had any issues with either.