I have had a wd mybook live for 2 years now and bought this drive for a backup.
Between the two NAS drives, the hands down better one at this time is the wd mybooklive (though mybook has a number of weaknesses too).
I'd recommend looking into Synology drives too as the ratings for their drives always seem extremely high - but they are much more expensive.
Firmware updates can greatly improve NAS performances so I recommend paying more attention to recent reviews.
Also, definitely buy NASes from stores that let you return open box items like Best Buy(though I'm not sure if on this item, they'll give me a refund - will find out tomorrow). You really need to try NAS drives out cause you really don't know how well they'll suit you until you try them.