I’d recommend the S&G 6600 series
My logic is that you want reliability over all else, and electronic locks reportedly have a lot more problems than good mechanical locks.
I agree with you that speed isn’t as important as reliability. For bump in the night, where speed matters, I have a few Fas1safe with simplex pushbutton locks throughout the house. But speed isn’t really a concern for securing the bulk of the collection in the big safe, which isn’t in a very accessible area anyway.