I never had any issues with mine but I have the older My Book Live, it is currently set to be my torrent client, + i also set remote ssh/scp/sftp access.
It is the backup for 3 phones, 2 laptops and 2 tablets. Using my own scripts for backups though, robocopy/rsync.
It is also my media server from which I stream to all devices mentioned aboved + a FIre TV box with Kodi
I did disable auto firmware upgrades and do it manually when necessary.
I also shut it down via the GUI or command line all the time. A few times the house power has gone out but it has been recovered just fine from it.
Now, this is not my first rodeo. But I remember having plenty of fun with my first ever NAS long long time ago in a galaxy far away.
Hardware wise, unit is fine. Software WD GUI, could be better. If you are a techie and willing to learn or already know some basic Linux, it is a lot of fun.
Mainly, it is a learning curve most people dont want to put up with, specially if it is their first ever NAS. But once you learn it, since most NAS regardless of brand are a some light flavor of Linux, you know what to look for and/or are getting into.
And last, for the price, it is the best NAS ever.
ADDED:
This seems like a very interesting option:
http://community.wd.com/t5/WD-My-Cloud/Clean-debian-and-OpenMediaVault-on-WDMyCloud/td-p/785505
