I've got three of these in a JBOD server, running a couple of months without incident. They're cheap, quiet, and low-power. They're not high-performance, however, and not ideally suited to RAID applications. Also, given the new sector size you can get dreadful performance from them if you aren't careful in setting your partition boundaries.
Having suffered the consequences of ignoring data safety rules in the past, I now make a practice of having three copies of important data in at least two separate locations. I'm frankly astonished that there apparently wasn't a differential backup process at the company. I mean, a month's down time, WTF? These hard disks are pretty darn cheap backup media if you've got lots of data (e.g. video files), but after this item I'm wondering if biodiversity should be among my archive criteria.
That the drives in question had "chemical degredation on the surface making the data recovery much slower and harder" is a puzzler to me. Perhaps there's something about today's drive materials I'm unaware of, but my CYA radar went off on that choice of words: someone screwed up during the recovery process would be my first suspicion.