This also somewhat implicitly confirms one thing I've noticed over many years of servicing PCs, mostly for others --- HDDs mounted in cheap flimsy cases seem to have shorter lives than those in cases made of heavier material.

Too bad they only tested 4 WD Blue (consumer/desktop) drives; I would've liked to see other models, particularly WD Black (high end workstations), Gold (datacenter), and Purple (DVR applications). The WD Blacks I use are noticeably heavier, and they do advertise them as having more vibration dampening.