Summary: I had other WD drives before and either the built quality is bad or I was just unlucky. The drive failed within 2 years. I replaced it with a Seagate that was much larger and seems more reliable.
Summary: This drive died within about 2 years of ordinary use (bad sectors, and files getting corrupted during any large file transfer). I had bought this to use as a backup drive in an enclosure, and it failed just as fast or faster than the one that came with my Lenovo ThinkPad (for which SMART reported failure; CHKDSK would freeze).
Summary: I bought this harddisk a couple of years ago to replace the 160GB harddisk that came as default in my Macbook pro 4,1. I found it to be a bit sluggish, but I was able to live with it for the sake of expanded storage space. Recently however, the harddisk has started emitting loud whirring sounds as if it is on the verge of breaking down. I am surprised especially since my laptop nearly never leaves the table on which it is placed much less subject to rough usage.
Summary: Was rattling around in the box, when received. Seems to be okay, but still... On another note: Requires a command-line hack to disable hard drive APM in MacBook Pro 2010; otherwise, it parks the heads every 30 seconds or so, leading to irritating pauses and shortening drive life.
Summary: Unfortunately for Western Digital, their quality standards seem to have gone down quite a bit. The Scorpio Blue drive is a good performer: fast, generally pretty quiet, and not very hot. It also did not affect my system's power performance at all. It was easy to install, and it's quite light. So what's the problem? Quality. Within six months, it had developed bad sectors and I had lost some of my data without even realizing it.