I’m fairly agnostic when it comes to the manufacturer, though I seem to use Seagate more than WD. And I tend to view the really negative reviews as being the product of a greatly uninformed purchaser who didn’t research what he was looking for or failed to read the directions. The people who don’t like something tend to scream the loudest. There are a couple of other brands I have looked at but these two are the top contenders in this class of device.
Both of the network drives have their own unique features and failings, so it’s fairly easy to compare them to my needs in some respects, and in the end they come out about even overall.
As to purpose, it’s primarily for backup with some file sharing functions between systems. I have no interest in remote access from offsite so the true “cloud” features/failings are not that important to me. I’m willing to sacrifice RAID reliability since it is primarily a backup solution and cost is a factor as well. My reasoning is that if either the primary drive or the backup drive dies, I can replace it and still have a good copy of the data. I also differentiate between backups and archiving. This is not for archival purposes.
All that said, the NAS aspect is sexy and all, but an external, direct connect drive shared from the desktop is also a viable option. I currently have a samba share on the desktop system that works nicely and may be the ultimate solution. There is no room in the box for an additional drive. The cheap NAS solution has just caught my eye a bit.