For what it's worth I prefer a push button with key backup as well as there is less that can go wrong, I was just saying biometric was the best of the two options. I'm a believer in KISS, especially when it comes to something like quick access to a firearm.
Neither. manual buttons.
But if I had to choose, RFID. Hands down for reliability. Biometrics have issues sometimes with fingerprints. An RFID reader doesnt balk if you hold the card/dongle/wristband wrong. RFID doesnt fail if you are wearing gloves. RFID doesnt fail if you have junk on your hands.
But both can definitely fail, with biometrics failing more often due to how the readers read your prints. Yes, you never leave your fingers somewhere else like an RFID tag, but they just are not reliable enough for me. OK, maybe a long gun vault, but definitely not a speed vault for the bedside table.