Looking for Recos on 3TB External Hard Drives

I've had only one external HDD, an antique 120GB WD. That puppy lasted me a good 11 years although I pretty much outgrew it after eight years. I permanently retired it (discarded it) early this year because it was mostly just taking up space and starting to grind a bit when spinning up.

I don't use external type drives anymore. They eat up more storage space, the larger ones require their own PSUs, and they don't seem to be as good of quality as internal drives. Internal drives are available with longer warranties and seem to give more bang for the buck. I have a couple of hot swap bays in my desktop rig, a 2.5" and a 3.5", that I plug internal HDDs into for making backups. I also have a couple of cute, little USB docks I plug internal drives into to make backups for my notebook. I use a modified, heavily padded transport case in which to keep a backup HDD and the original HDD from the notebook (I replaced it with an SSHD a month or so ago); the case and one of the docks (I keep the other in my desk drawer at home) fit into my notebook's case with a bit of creative arranging.

I feel the internal drives are going to more reliable, more economical, require less storage space, and, with the exception of the ones for the notebook, which get infrequent use, are more convenient to use.

As far as brands go, the only real games in town for HDDs are the WDs and the Seagates; the other brands are owned by one of the big two. Both get similar user reviews and each has had their bad batches. Although I favor the WDs, the best way to choose before buying is to compare the recent reviews of both to see if one is having a bad run. Other than that, the only real criteria to consider are price and length of warranty. For external drives, I suggest only considering those that are USB 3.0 compatible, even if you don't have it available on your machine; someday, you might and you don't want to be hampered by a slower buss. Same for getting only SATA III. It's all about future proofing. If your machine has an e-SATA port on it, then an external drive that is e-SATA compatible would be nice.

Edit: Steve and you crossposted while I was posting. I use WD greens for my backup drives. They don't hold up as well as the WD Blues and Blacks, based on reviews, but, since I run them only for backups around once a week, they should last a long time. If you use yours heavily, then I recommend the Blacks (I don't think WD makes a 3TB Blue, which would be a better choice for intermittent heavy use). I do have some Blues I was using to backup my boot drive until it dawned on me that all I needed to do was keep my boot drive images in a folder on my main data drive, then they would automatically be backed up when I did my weekly data drive clones (I prefer to clone my data drives to back them up so accessing data is easier if the data drive itself or the computer dies; I have a dock for the latter scenario) without any extra effort on my part.

Whatever drive you choose, don't let it be the only repository for your data. You should have your data in no less than two different place: the original and a copy. Two copies of the original, one onsite and one offsite, is much better. I have three HDDs for each HDD in use for backups. Two are kept onsite and one is kept in a safe deposit box at my credit union (that one gets swapped out at least once a month). I also use Carbonite for an additional offsite backup that I also can access for data retrieval when I'm on the road so I don't have to carry all my data with me.
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