It was great, until WD decided to update the firmware...
353288
I used to love my drive and ran extremely well for my needs. It all went downhill when they decided to come up with the v04.04.00-308 firmware update... everything stopped working, the 'shares' were completely inaccessible from anywhere in my network and I even went as far as creating completely separate network to try to recover my files to no avail. A couple of weeks after that dreadful firmware update, WD came up with a new one (v04.04.01-112) which promised to fix all the issues (the WD forums are flooded with posts about issues after the v04.04.00-308) but the connectivity issues persist and the browser UI is virtually inaccesible and it hangs and never completely loads (see screenshot).
Of course I have tried contacting their 'support' and the only answers I get are things I have already tried, like resetting, resetting to factory, etc. There is no sense of urgency to try to solve the issue.
3353245
I had the WD for about a month then all of a sudden my home and laptop computers no longer recognizes it as a drive.  I have tried many tech supports and all say I am screwed and my data is lost.  WD will replace it though...cool to bad I had 300gb of info on it right!
2711955
it is working great, really , all but the FTP service sometimes fail, and you need to restart it (they actually has an option to restart the fTP service - I guess they knew it is going to fail sometimes)

one note, the minute you get it, download the latest version, it comes with such an old firmware that the FTP / WiFi, or any other ethernet service is just not working, it is not even look like the screenshotes in the help, once you upgrade everything is great.

It crushes many times, in the middle of a movie, and the system need reboot,no version upgrade exists,espcially it crush when using an external USB HD.
3050335
I installed the SSD sometime around October 14. I was really happy with it until May 23rd.  All was well until I woke up that morning with some strange boot message. A soft reboot still wouldn't recognize the SSD. A cold boot later, and it was up and running. Okay, that's weird, I hope it's not dying, off to work. Same problem again when I got home, reboot, fixed. An hour later, BSOD and the same problem again. It turns out that there was a firmware released in January that fixes this problem. The firmware update process was painless, but the BSOD that came before that had me nervous for a little while.

If you're running firmware 0009 or earlier, make sure you update. Another reviewer said something about a cold reboot not fixing the issue, I think he might've had some other problem. The drive will continue to work without the firmware update, but Windows 7 will BSOD every hour until you get the update.

I've had this drive for just over 10 months and the only issue I had was the BSOD/firmware issue. It's quite fast and hasn't lost any data yet.
1031220
**Update 2/10/2011**  Another RMA for all three drives.  I just spent 2 weeks rebuilding my RAID, restoring and re-backing up my data after the drives corrupted all my data.  This is the 4th set of drives for me.  They are upgrading them to the 2003 version that has the set 72000RPM speed to eliminate the issue with drive timing issues.

**Update 1/10/2010**  Western Digital swapped out my old drives for the newer version which seem to handle the read/writes and spin rates much better.  I had to rebuild the RAID for each drive replacement and copy my data over for backup (about 1.5TB including some large video files exceeding 15GB).  Transfers were seamless and rebuilds went without a hitch.  The new version is WD2002FYPS-02W3B0.  Make sure you get this firmware version when you order.  They do seem to fix the issues I was having.  They have only been running for a few weeks and time will tell if they end up with the same read errors the older version drives had, but I feel better about these.

Original review:

I purchased 3 of these drives to create a RAID5 array to give me 4TB of storage for my work and personal files.  I immediately had issues with the drives due to spin rates and compatibility with RAID controllers.  It took work from both the RAID controller manufacturer (Areca) and WD to get firmware updates to allow these drive to sync their spin rates with the controllers read/write requests.  During that time, I had the drives fail 5 times.  Once we got the firmware issues resolved, I thought all was well.  Now about 6 months later, 2 more drives have failed within 3 weeks of each other with the same read/write issues I had previously.  I have confirmed that it has been the WD firmware each time.  WD refuses to acknowledge issues on their end, so it has been up to me to resolve all of the firmware issues.  I think Areca wrote several firmware updates due to my working with them on these drives and their controller to try to work around WD insistence it wasn't their issue.  Finally, Areca and WD got together and WD finally came out with the correct firmware to fix the spin rates and timing to work in RAID.

I can't afford to pay as much as I did for these drives and have them fail more frequently than any other drives I have owned or sold.  They are supposed to be enterprise drives and provide millions of hours of up time.  I'm not getting thousands of hours of up time without failures.  These drives had manufacturing issues from the start with all the posts I have found with similar issues as mine.  This is not what I expect from what are supposed to the the flagship of drives from WD.  I am in the process of returning all the drives and looking for other drive options for my RAID configuration.
740995
I started out loving this router and the functionality of it but after taking advantage of those features as a wifi nerd and power use of my network, the firmware starting crashing and freezing. 7 months later, I'm tired of factory resets and a lack of firmware updates for this model. Now I'm shopping for another. The features are rich and amazing if only the firmware worked and wasn't so buggy. It comes with the power user in mind but the features are apparently for show only. I'm rethinking ASUS purchases in the future.
554808
I've tried twice via email to get support from WD and as usual, they're putting the blame on Microsoft rather than providing a fix. Vista doesn't recognize the drive. Yep, time to switch brands!
2252315
I bought this piece of junk in the last part of 2014 and it worked for a while. In the past two years or so the network connections have been failing almost daily and sometimes several times a day. This has resulted in my nightly backups not running consistently or dependably. After searching the internet for ways to resolve this issue I have found that Western Digital as been aware of the issue for a LONG time and has not fixed the problem.  I have used DHCP and Static IP and have updated firmware as it has become available but nothing works.
This week I ordered the Synology DS216J NAS DiskStation (DS216j) and moved the hard drives from the WD Mirror into it. So far this is working like a dream the DS216j has a great deal more to offer in terms of utilities and media server programs and is less than half the price of the WD enclosure.
4311408
I have bought two previous WD My Books External hard drives and am still very happy with them.  Yesterday I happily bought my third one and was very let down with their "New Smartware"  It's junk.  I hate this lame software so much, I am done buying WD! It's a shame I love their hardware, but this new software SO pisses me off!
3571006
EDIT: *************
WD has gotten in touch with me through my RMA, and has sent a replacement. Replacement seems to be working just fine.

Old Review:
Mine has failed. I am RMA'ing it now. It was screeching like a monkey when I tried reading from it before. Now that I'm RMA'ing it it seems fine. I hope that they can see the problem. I'll update when I hear what wd has to say.
1596847
Full disclosure: I am a die-hard WD hdd fanboy. MyBook, MyPassport, My-internal-WD-hdds, even my Lacie Porsche Design is built with a WD inside. I pick WD drives as Christmas gifts for my data hogging friends.

Naturally I was excited to try out a WD router after years of running my old Netgear WGR614 - yeah that ancient and super reliable one.

The key justification for an upgrade besides the low price was the USB HDD sharing feature, which turned out really, really messy. In my case there's more headache than happy family time streaming HD "video to multiple devices". For a bonus the router wiped nearly clean one of the two HDDs plugged into it full of media stuff intended for sharing.

WD support is not as good as it used to be. About 1 hour of bouncing up to level 2 and I'm still working on a solution.

Update, October 2013: No real solution was found to recover my data. I ended up picking out some of the lost files in raw mode (no file names, no folder structure) with free file recovery utilities, but most data is gone for good. WD support weren't able to figure out what had happened and why the router wiped the HDD clean, nor did they help with recovery.

The good news is that my other drive's data is fine and streams okay over the past couple month.

Also, I had to disable FasTrack Plus and legacy 802.11b support to get a reliable wireless connection. One of my family laptops was dropping the 802.11g/b 2.4GHz connection. My HP EliteBook is steady and fast online on the 5Ghz. Got to love the dual band and MIMO patch antennas! Oh, and as other reviewers had noted the built in fan is never on.
4846163
Welp you won't have to worry about the firmware. MSI's website makes even finding this router hard - and no downloads to be found. Forget about dd-wrt & tomato too. But the real problem, and why I'm now on a D-Link router, is stability. The router needed to be restarted at least daily. My old Belkin (F5D8230-4) was rock steady. It was so very reliable I thought my cable provider was the problem for a while. Nope. It was the RG70A router. Sometimes I'd be restarting the MSI nearly hourly. Now I'm stuck with another paperweight. I can't sell the MSI and I can't think of anyone annoying enough to give it to.  Take your time and save your money until you can afford a good quality one. I've got a D-Link DIR-655 now ... and a rock steady 801.11n with WPA2 security WiFi network
4744362
The NAS kept disconnecting from the network during large file transfers.  After speaking with a rep I was told it would be fixed in an upcoming Firmware update, with no ETA... Steer clear of this one folks, don't let the price fool you.
1107222
It was great for about 4 months, then it died. Windows said it needed to be formatted; I initially thought I lost all of my data. Luckily I was able to download some software to recover most of the files. The recovery process was a real pain, and I lost some very important work. I loved the size and thought it was very fast. If I had written a review of it a few weeks ago, the review would have been extremely positive; reliability is a must with usb drives, thus losing data after just 4 months is unacceptable.
1432089
Had this for about a year and loved it....then I just went to reconfigure for Fastlane to get better performance for HD streaming on my smart tv..when I went to reconfigure I saw there was a Firmware update.  I updated the Firmware and installation was successful.  Suddenly the network disappeared and I lost internet connection.  when I looked at device it had a blinking power light and no longer works.  This device is only a year old.
299496
Like most WD products it worked great for a while, but then for some unknown reason, after a bit, the computer no longer recognizes it when it is plugged in.  You have to constantly try to wiggle the cable and god forbid if you move your laptop just a little while its plugged in, it disconnects.  Very annoying.  And this is not the first WD HD to do this to me.  I thought the first one maybe had a glitch, so I purchased this one but got the same problem. -.-
2663899
I recently tried to upgrade the firmware on this drive and now the drive is a retractable cupholder!  I've got a LOT of experience with things like firmware upgrades and followed the instructions to the letter.  The firmware update program said that it completed successfully and I figured I'd be off and burning again.  Now the drive won't even recognize a commercial pressed CD.  I tried installing the drive in another machine as a check and it was dead there too.  Yamaha used to be "The Brand" and all I'd buy.  Now I'm done with them.