I have an AOpen drive here that fails the upgrade, leaving the drive dead. The first two times this happened, I returned the drive for a new one. Now with the third drive, I have a sticky note on the front saying "do NOT attempt f/w upgrades!".
Some brands can be recovered regardless, but not AOpen. I used Google to find all sorts of links for this, including links to a recovery tool. But that was a year ago, and I no longer remember much more about it, other than that it exists and works for most brands of drives.
Cheers