This is, by far, the most robust external hard disk I've ever owned. And, when I say solid, I mean almost 3 lbs. solid (I didn't put it on a scale but it feels that way), 100% metal casing, likely to survive a building collapsing on top of it. Given that I bought it for backups, not for travel, I actually like it this way. I like it very much.
It's probably helpful to enumerate the features I feel are worth being aware of before one buys it (and I shall answer any additional questions if you drop a comment, to the extent that I can):
# Heavy, solid build, almost bullet-proof enclosure.
# 8"x4"x1" rectangular prism (these are not exact measurements but I'm confident it's close.
# USB port for data transfer, cable included.
# External power supply.
# Silent run - you can't hear it spinning unless you place it close to your ear.
# Cool - after one night of uninterrupted operation it was barely warmer than room temperature.
# Not a speed demon but I backed up 50GB in something like 20-30 minutes.
# Formated as FAT32.
# Comes with no software but it was instantly recognized by both Vista and my PS3 (more about that later)
# There is no manual to speak of - and no manual is needed.
# One year warranty.
# 30-day free tech support during the warranty period where the clock starts running after the first call to WD.
# Lacks the (to me annoying) carnival lights that some other drives have these days - only one blue LED, on the back, blinks when read/writes are performed.
I can't think of anything bad to say about this device. I went for the 1TB size because I wanted to back up several smaller computers on it and my 320GB PS3. For a stress test and if you are going to use it with XP or Vista you may want to reformat the disk as NTFS - Microsoft will be spinning your disk for many, many hours and, if you bought a dud, chances are it will stop working during the 10-12 hours format process. Or, you can check the 'fast format' option and the formatting will be done in less than one minute.
After the overnight test was passed, I partitioned the disk into 4 using Vista (no problem whatsoever) and I formated 3 of them as NTFS and one as FAT32 (get FAT32FORMAT off the Net because Microsoft's utility does not work on a 300GB partition). Backups ran flawlessly with Microsoft's backup interface and backing up the PS3 was incident-free too - it instantly recognized the FAT32 partition and I have a nice PS3 backup now.
I highly recommend this drive as a backup device that does not travel a lot.
P.S. - if my review seems to be coming from someone who uncritically gushes over little gadgets, do check my other reviews of electronics or my reviews in general. I am trying to be as objective and as factual as possible and, in this case, I believe, we have a good, solid device that fully meets expectations.