I found this drive; http://www.amazon.com/gp/product/B00...SIN=B003S6ID20

is this a good one?

also, would it be safe to get the $90.00 one from amazon; http://www.amazon.com/gp/redirect.ht...reative=390957 they are used, but they have a fulfillment by amazon, or should I just get the new ones?

I have been using a 1TB hitichi deskstar with no problems yet.

and using it with or as the backup or swap drive with this one that I was suggested; http://www.amazon.com/gp/product/B00...SIN=B001UE8LRE

I read that some people prefer to use a drive one each from different makes/brands, is this a good idea? or should I stick with 2 of the same brand and model? does it matter?

I like the look of the western digital green, but I got nervous when I read about what seemed to be too few instances of failure on newegg; http://www.newegg.com/Product/Product.aspx?Item=N82E16822136344

It's not a "bad" one. I would simply suggest Western Digital has proven itself to be a better drive. And the WD drive is only $99 + $4 shipping. But if you want a Hitachi, go for it. It's a good drive, too. I have some Hitachi drives, and these have been fine.

I would buy the new drive, since this is for archival needs.

Same here. 500GB, 640GB and 1TB have all been fine.

That sounds like a good idea.

Generally speaking, you reduce the margin of "duplicated errors" by using two different drives, from two completely different manufacturers. Should one drive prove to have some kind of fatal flaw, the other drive is unlikely to suffer from that same fate.

You never know what boneheaded thing somebody may have done, so remember to NEVER TRUST user reviews left on shopping cart sites. While it can be good for identifying specific trends, it's also a hotbed for morons to demonstrate their lack of knowledge, skill and competence. Many, many negative reviews are left because a person has not followed instructions, or has mishandled the item. Finally, merchants and devices are often blamed for shipping-related errors (exposed to radiation, x-rays, extreme temperatures, etc). That, of course, should have no bearing on how good a store or product actually is, yet those are what the reviews blame.

As the old saying goes, "take it with a grain of salt". ;)

various shipping circumstances have me thinking, are there any things I should do to check for functional problems when I get my hard drive before using? if it was exposed to extreme temps while in transfer, (it is still winter), although I am in California, but if I order one from say the midwest or east in the US, should I leave it at room temp for a bit? or run disk checks on my mac? etc this sort of thing?

Always. Changes in temperature and/or humidity can cause condensation to form. And while it's not good for a device, regardless of on/off status, it's best to leave the device OFF while the condensation evaporates. Hard drives have small holes in them -- they are not air-tight or even water/liquid proofed. (Excluding a few specia;/expensive "tough" drives that are on the market -- mostly for gimmick, as far as I'm concerned.)

Aside from that, no, nothing you can really test. Turn on the drive, see if it works.

how long would the for a bit be? should I leave it in the box or shrink wrap? or take the bare drive out & let it sit?

You can open it, sure. Just be careful not to subject it to static electricity, put it on bare carpet, etc. I open drives and set them on a wood desk surface for several hours.

If I use hard drives, or mirrored hard drives as a backup, say for instance I have a hard drive stored somewhere for a few to several years & it is not connected or started up at a computer in that time frame, will it's components have deteriorated? will it rot out?

like a car, does it need to be started up periodically?

I have some older 250 gb PATA IDE Iomega external hard drives, will they rot out?

A car needs to be started periodically because it has chemicals in it that can go bad: gas, oil, grease, fluids, etc. Those can change consistency over time, the non-elementals can break down and separate, etc. A hard drive is mechanical. No, it cannot "rot" in any sense of the word. By "a few" we're only talking 5 years max, too -- not decades. After a few decades, yes, drives may have issues from decomposition of the metal alloys. It's possible.

If you have read something to the contrary, you're being fed misinformation. Here's a great example of utter bollocks (BS):
(Note: I don't link to crap. You'll have to copy/paste it to your browser if you want to read the article.) "Magnetic fading" is a made-up term, as used here, as quoted from some anonymous source. Somebody is confused. I would have to suggest that Mr. LJ is gullible to have believed that garbage. It's rather sad when people spread this sort of garbage online. This is the same sort of horsefeathers that is spouted by amateur video conversion services that insist "your tapes will fade" if you don't (wink, wink, nod, nod) get them converted right away.

Tape-based magnetic media has a lifespan of "only" a few decades, but that's because of glues, binders, chemicals, etc. In other words, it's like the car. Chemical changes. Non-chemical hard drive platters have no such affected systems. Hard disks give out because of wear to the motors, the arms, needles, etc -- basically hard drives wears from use, not inactivity.

The only reason hard disks are not tested for this length of time is because the tech obsolesces so quickly, within 5-10 years. Newer drives use different tech, and are most often completely incompatible with the previous generation of hardware. Even industrial computing items like ATMs, which often have last decade's hardware and software powering them, tend to be refreshed every 10 or so years. Data is easily moved to a new disc, because unlike tape "formats", the disks just hold data. The data is not formatted in a special way that forever binds it to the media, like VHS. There's no incentive or reason to extend the life of hard disks forever, by replacing motors and arms. Hence a complete lack of research. Which in turns allows for asinine claims about "disk fade" because nobody has wasted their time on contrary (more factual) research.

are there any special conditions that a hard drive must be stored in? if it is not in use in a computer or as an external? can components oxidize?

it seems then that the connector types on a hard drive might be an issue, if I have one in an enclosure with usb & firewire, I know no one can see in the future but, will I be able to connect it in several years after being stored? will there be adapters if the connectors become obsolete? will SATA be obsolete & will there be adapters for old tech?

Indoors.
Normal temperatures (60-80 F), normal humidity (not a green room) -- just a normal human living/office condition.

Adapters for old drives? Not usually, no. At least not historically.
IDE/SATA was an exception. That one is bidirectional!
USB 1.1 to USB 2.0 to USB 3.0 for external, same basic plug/comm setup, was an exception. Also bidirectional.
Firewire 400 works on Firewire 800, with plug shape adapter.
Reverse compatibility has gotten better with time.