The problem with fireproof drives is that pretty much every fireproofing uses gypsum and that insulates the drive, so they will tend to overheat quickly, unless you let air through, and that tends to defeat the fireproofing.... Of course they say "it will seal off during an actual fire" but I wouldn't trust that myself.
Personally I use a quick swap drive and have 2 drives that I rotate into an actually fireproof safe that I have in the house. Other documents etc (birth certificates, etc) go into the safe, so it serves other purposes and it's still -relatively- easy.