I didn't expect someone would review $299 device (excluding possible import tax and shipping cost). But with such high cost, i'm really annoyed they don't bother include rechargeable lithium AAA when they include industrial class microSD.
- microSD: This is a method that the Passport itself offers, but I find very risky. As soon as you insert an SD card into a computer, basically any process and any unprivileged app running on it, that has filesystem access (most of them, even the browser..) can read and modify the contents of that SD card. It should be pretty easy to write a background program that waits for SD cards and replaces PSBT files on the fly.
IMHO, if people choose FE rather than other hardware wallet (such as Ledger and Trezor) which is cheaper and easier to use, it's more likely they have better secure practice. I wouldn't worry about malicious application which replace PBST file if you perform good security practice and verify the transaction before sign/broadcast process.