it's a complete load of rubbish
hd floppies can last as long as dd floppies
in fact there are not technical differences between them ..only a hole
to store the floppies of course a sealed box away from moisture
otherwise they can get fungus like cd and dvds
Longevity-wise, no, there's little to no difference, except that today the quality as a whole is quite a bit less in the manufacture due to their reduced popularity and sales. For instance, old micro-disks had a dust jacket through the entire internal surface, whereas now there's just a single patch -- arguably this is less effective than the full jacket.
However, there are technical differences between the two.
