From the link that you posted, I don't really think that there's a huge difference between WD and Hitachi in terms of reliability, they both seem good enough. As one poster noted, all companies have one disaster model every now and then (I've been the 'proud' owner of four 75GXP deathstars), so what really matters is consistency, and both seem to be pretty consistent (bear in mind that Backblaze have about five times as much experience with Seagate or Hitachi as WD).
As for the Greens, I can see why they'd be more prone to failure under conditions of intermittent loading. In the big scheme of things, I can't help but think that the energy savings are fairly trivial for the sorts of uses we'd have.
Of course, the "5s" referred to by your correspondent is in fact the Se.
And he has now purchased four of them, and a nice little NAS to put them in. It's only taken him a couple of years to make this decision, bless the little cunt's little cotton socks.
bastard by name