Western Digital was around before Seagate even was, BUT, Seagate just bought Western Digital. When Seagate bought Conner Peripherals, guess what happened. The quality of Conner's next hard disk (A 1.2 GIG drive at a cheap price) was SO bad that EVERYONE's 1.2's died within a year, with most not making it past 3 months before they filled with bad sectors and became comepletely un-useable. The drives that were sent back to the customers who DID RMA their quickly failed brand new disks were even worse than the original drive, because they were DOA or full of bad sectors, and the bad sector counts were climbing substantially every moment they were even running, just like the drive they sent in for repair or replacement. Some even sent drives back 3 or more times before they gave up.
Conner then bankrupted and closed, but I guess Seagate made out okay. In fact, they now not only had one less competitor, but had used to profits from the faulty drive sales to off-set a good portion of what they paid to acquire Conner. The next company Seagate bought, which like Conner, had a very decent product BEFORE Seagate bought them, was Maxtor. I'm sure you never heard of them either. Yup. You guessed it. Seagate did the same thing there, only just not as fast this time. Maxtor also went out of business after their drives slowly began to fail more and more frequently.
The Federal Trade Commission looked into this mess, but apparently "did not find evidence of any funny business," as everyone THOUGHT the certainly would. It was just a coincidence I guess. (Really?)
Guess who Seagate now owns.
Western Digital.
Given the three options you have, my next questions is, what is the price difference between a WD hard disk and an HGST?
Now, as far as your statement about great drive that never fail being unlikely in the foreseeable future, your right, but there are an awful lot of VERY old drives that still run fine with ZERO bad sectors. The trouble is, a 40GB drive is useless!
I run Windows 7 on a 128GB Samsung 840 Pro with the programs I need to launch often and quickly installed on the C drive, and stuff that doesn't require SSD speeds or that I don't use often installed on Drive D. My Desktop is also NOT on drive C, because I tend to sort files on my desktop in folders before moving them to their final archive locations on a regular HDD, and some of the files I sort though are quite large. (Uncompressed wav audio tracks and large video files being the largest) So, there really isn't a great reason to hammer the SSD with huge files that are only going to be there for a short while before they wind up in a directory on a hard disk anyhow.
The same can be done for all the "MY" folders is you use those. You know, like, "My Music," My Videos" "My Documents" etc.
That allows you to run a good FAST SSD that boots SO FAST you actually travel backward in time without a need for a Terabyte drive. It's not really FOR storage you know! Movies and music don't play so fast you need them on an SSD!
Games and other programs, however . . . yeah. Fast is definitely good.
I'm poor too, and when I have to eliminate food from my budget, I find that if I rinse my socks out and ring them into a bowl, it makes sort of a broth if I get crazy and start longing for some sort of nourishment! It's sorta salty!
)~ Add a couple carrots and a little onion and like magic, <<<POOF>>> IT'S SOUP!
Seriously though, I have never had much money beyond what I need to pay my bills, adn that's still the way things are. So the few things I DO buy to make life a bit easier or more enjoyable, be it a pot to cook my "soup" in, or a new HDD, that will be all I can afford after saving for several weeks if not a few months, I tend to make sure I buy things that will last as long as possible. I can't afford to buy things that break quickly only to buy the quality I SHOULD have bought in the 1st place.
As far as the Seagate being in an external case and transported, if it's not running, the heads are parked, and in that state, a drive can endure shocks of something like 200G's. If you carry it in a backpack that's certainly better for it than in a basket or on a bike rack, but even at that, yeah, it definitely can "help" a drive fail sooner.
As for your power on count, it is actually quite low for a home user. Many people turn their computer off every time they walk away from it for more than an hour, and they have very high counts. I, like you, leave my machine on unless I need to restart or shut down to do something, or unless I am not going to be home for several days.
My 2 2TB drives show 1601 power cycles and 60,832 hours (2335 days) on one, and 1682 power cycles and 41,817 hours (1,742 days) on the other, and my 4TB seems to have SMART turned off. Hmmm. I think I turned SMART off on that channel when I had my little 1TB Samsung in the box. That drive has a known issue of falsely reporting that it is failing under Windows when it is not. There was never a firmware update for it, so most just shut off SMART reporting under Windows on that drive, because it's fine. Windows has been saying that "that drive" "might fail" and warning me to "BACK UP NOW" for something like 8 years. It still runs fine and has never lost any data. So, go figure. It's a known false report.