Now this is something I can definitely be a help with!
The failure rates for high density drives (1tb and up) is the result of a mixed bag of misunderstanding HDDs and poor production by some manufacturers (ahem, seagate
). I have over 8tb worth of space between my computers at home, and I can tell you first hand that high density drives can be are quite reliable. As density goes up more information is squeezed into smaller spaces on the disc and the likelihood of imperfections in the surface of the drive goes up. Many drives ship from the factory with some bad sectors. But don't freak out, all modern drives has "reserve sectors" which when your HDD detects a bad sector it reallocates one of the reserve sectors at the end of the drive to its place add this is completely transparent to the end user. (these appear under a S.M.A.R.T. test as reallocated sectors). Reallocated are very common on large drives and a somewhat rare to find a drive that doesn't have any. The thing is alot of people see reallocated sectors and don't really understand what that means or think there drive is failing. Now i do know that many of the so called "green" drives by seagate have had a terrible reputation for having uncorrectable sectors, mass numbers of reallocated sectors (which is a problem) and all other kinds of problems that seem to suggest the downward spiral toward HDD death.
In regards to SSDs vs HDDs in terms of dependability, the truth is no one knows yet. SSDs major benefit is that they are faster (well techinally the time it takes to read the information is slower the a HDD but they have almost no seek time, which adds up in the end to be faster). One thing to note is that SSD are flash based, and NAND storage can only suffer a limited number of read/write cycles before its toast. Most modern SSD are SLC and not MLC (like your flash drive which only has about 10,000 write cycles), which like Doug said has between 1 mil and 5 mil write cycles depending on the wear leveling and other factors. This was a HUGE issue a few years back when this would mean SSD might only last 3 years before running out of cycles or less when used by powerusers. By comparison HDDs have an unlimited number of read/write cycles and potentially can last something like 34 years if left on constantly for 24 hours every day. Each HDD milage will vary. I've had a HDD thats still running in an old 95 system thats 16 years old now (not that its useful for much anymore though. Technically after a SSD has reached its max number of write cycles that block becomes read only, meaning you can see information on it and open it but its burnt out and you cannot write anything else to, but SSD drives rarely fail due to having come to the end of their read write cycle life and are more plagued by other issues. SSDs are actually more likely to have sectors go bad, but their isn't a performance hit when it reallocates sectors like there is in HDDs because they can read anywhere on the drive nearly instantly whereas when a HDD has a reallocated sector the drive must jump to the end of the drive where the "replaced" sector is and then jump back. Ultimately, even Intel admits that SSD are too young to be able to paint an accurate picture of how dependable they are long term. Personally I prefer a 7200 rpm HDD to a SSD for my computers because I can't justify the price difference for a drive thats likely to be 3 to 4 times smaller. On HDDs are less then a $1 per gb these days. Statements from SSD manufactures stated that they do not expect SSDs to come down in price for another 5 to 10 years. That said I have wanted to get a USB 3.0 external SSD.
In looking for reliable external HDDs, you cas make your own! You can usually find drives marketed as "internal hard drives" to be cheaper and higher performance then external drives, and you can buy and enclosure on amazon for under $15 and... voila you just got a 1tb external drive for $70. Drives are cheaper now then they have ever been. On Amazon you can get a 80gb external hdd (in an enclosure already) for $30 from cirago, and 160gb for 35 and a 250 for 40 here:
http://www.amazon.com/Cirago-Portable-External-Drive-CST1080/dp/B001CBLN7K/ref=sr_1_1?ie=UTF8&qid=1304803185&sr=8-1. I have one of these that I have had for about a year now, no problems what so ever, and these are bus powered 2.5 drives so they are portable as well. Cirago basically just takes OEM drives and puts them in and enclosure puts their own warrenty on it and ships it.
If you guys are looking for fast HDDs as a external drive then you should get a drive that 7200 rpm as that will make a impressive difference on file transfer speeds. You may also want to check into getting a usb 3.0 external drive (you'll need to buy a expresscard or pci card for your computer if you don't have built in usb 3.0 ports which most people don't). With USB 3.0 and 2 2tb 7200rpm external hard drives each drive could process 120 MBps (thats bytes not bits). AKA, likely faster then your internal SATA drive in your laptop. I personally recommend the Buffalo DriveStation. I have two of them and they utilites they come with are worth it alone. Beside having USB 3.0 makes you the coolest kid on the block
.
The fastest drives on the planet are "RAM disks" which is really software which allows you to take a chunk of your RAM and turn it into a storage medium. Here I got speeds of over 7000MBps (~100 times faster then the typical 5400rpm HDD).
Most RAM disks offset your information to the Hard disk when you shut down the computer and put it back on the RAM disk when you start it up again. Obviously the limiting factor is how much RAM you have to spare to turn it into a disk. Now maybe in a few years they'll have "L2 cache disks"
And yes data recovery really is highway robbery, especially when you consider the tools they use to recover your data are only around 1000-2000 bucks. You don't know how many people I have seen go into Bestbuy for HDD recovery on a drive that had nothing wrong with and it was the motherboard that failed or the SATA controllor or worse just a software issue and because they don't know how simple it is to by a $5 enclosure and do it themselves for free end up paying whatever premium price they charge. If you can assemble a chair from Ikea you can take a hard drive out and put it into an enclosure.