All the HD80 SCs used by Apple have the same level of firmware (Quantum ROM
rev. B). The quantity of bad blocks may vary from one disk to another, but
this is transparent to the user.
More specifically, any Apple HD80 SC can be formatted for use with either
A/UX or the Macintosh OS. It is possible that drives displaying larger
numbers of bad blocks are older drives and, therefore, have more bad blocks
due to time. However, all of the drives should format to the same volume
size under either operating system.