That's going to be pretty subjective. Whoever made these drives may have to best coating on their drives measured by how well they retain data when overheated. Gaining that may be at the expense of data capacity or access speed. Unless you can afford what it costs get data off a failed drive, for backup media you'd probably be better off looking at criteria like the reliability of the electronics and mechanical components, than the thermal resiliance of the surface media. MTBF is supposed to be an objective measure of that, but I take weigh manufacturer's numbers against their reputations.
“As I’m planning to buy some back-up drives and all I get is double-talk “
Not sure that it matters today. I worked for HP’s disk drive division for many years before I retired. I don’t think this one was an HP design but it doesn’t matter at this point. All of the patents are shared between major manufactures. And HP is no longer in the disk mech business... They had superior quality, but couldn’t compete on the price.
That NASA 340MB drive was made by IBM, which is no longer in disk drive manufacturing business - they sold it years ago to HDS / Hitachi Data Systems - though they still do great research in magnetic (specifically, vertical), optical and hybrid storage and memory, particularly in density area.
As I'm planning to buy some back-up drives and all I get is double-talk on which are the best/most-durable.
Most media / drive platters are made by third parties and used interchangeably by most remaining drive manufacturers. Depending on size of the drive (3.5", 2.5", 1.8") you will not go wrong buying either Seagate / Maxtor, Western Digital, Hitachi / IBM or Fujitsu. The differences for the most part are insignificant unless you really know what specifically you are looking for that another brand drive doesn't have at the moment. If your computer has SATA interface, I would suggest going with SATA drives.
Unless you need great speed (unlikely for purpose of backup) I would recommend staying with 7200 RPM drive instead of 10K or 15K RPM enterprise / multimedia drives due to lower heat and higher media reliability. Ignore all manufacturers MTBF claims, warranty duration is far more important. Smaller sizes or removables have other, lesser known names which sometimes are only branded differently. I would generally stay away from those unless you know the company / brand and have specific reasons, other than price, to use them.
Hope it helped.