reapersaurus said:
wow.
amazing rant/fantasy. 
You missed my point:
I'll rephrase.....
When 1 TB HD's are available, it's a guarantee that 500 GB HD will be more commonplace, and more than 1/2 as expensive.
You could most likely get 5 500 GB HD's for the price of a TB HD.
Now, if the AMOUNT of space is the most important factor, then you would always get multiple smaller HD's, if $$$ are a concern at all.
If the PERFORMANCE of the drives are the most important factor, you would always get the smaller drives, and place them in a RAID configuration, so as to revel in your HDTV goodness.
If the RECOVERY capabilities of the drives are the most important factor, you would choose a fault-tolerant RAID configuration, so if anything happened to all that lovely data, you get recover it without much problem.
^^^^^^
1/2 = 1/5 ?????????
So when I buy these 5 500gig HD's I'll have the equivalent of a 1 terabyte drive? I'm going to assume that that is a typo and you meant 5 200gig drives. If it wasn't a typo then it makes no sense from the start.
Lets just check with pricewatch and do some comparisons..... gee a 20gig EIDE HD is listed at $51 a 100gig EIDE HD is listed at $99, so for you to get 5 20 gig HD's it would be $255, this is the normal trend for EIDE HD's. Now you could be talking about SCSI but it is dying and probably won't be around much after serial ATA. Yes when they are first introduced they will be much higher priced (a 250gig HD cost $388) but high end drives go down pretty quick from there (a 200 gig HD is $242 an 160 gig is $189), once they hit $100 or so they don't go down nearly as fast. Yes the ratio's vary, 2 100 gig HD's are less than 1 200 gig HD, but 5 40 gig HD's are $320 (or $78 more). Your logic might apply for the first couple of months or so but once terabyte drives get main stream it falls apart where price is concerned and a year or so after they come out there will be no arguement at all. Oh and lets not forget that for the most part much smaller hard drives are older and normally slower (it's hard to find a 20 gig ATA 133 drive).
That takes care of the amount of storage space for cash, now what about the amount of real space, well 5 HD's are bigger than one HD regardless of how much information they hold, so if actual space is a issue (such as with smaller computers or laptops or TIVO sets) then having one HD wins.
As for performance, well not always does raid win, it depends on how you have raid set up. Are you running them stripped in raid 0 or running raid 1 or 0 +1 (or other settings if you have SCSI). If you are running raid 0 (which you would have to be doing if you want 5 200gig drives to equal 1 Terabyte drive) then you will get some impressive speeds (read and write speeds may vary but they will be pretty good) but you have also increased the chance for a catastophic failure, if one drive fails then you loose everything the information is written across all the drives like they were one drive. Raid 1 or Raid 0+1 would need a even amount of drives (would a ATA raid setup even run 5 drives?). So to use RAID 1 (which is mirroring) you need twice as much space (you are writing the same information on two different drives). What you want to to get the speed and the protection would be RAID 0+1 which would require 10 200gig HD's. How is that in any way logical for the average user? How could that possibly be cheaper?
Also lets not forget that RAID is for high end users who know what they are doing not for the kind of people who never open a computer up or mess with the settings (which is the vast majority of the people out there). I really doubt we will ever see a RAID TIVO set, which is the most likely source for the need to record HDTV.
Oh and lets not forget that for video if it will record it and play it back at the speed that you are watching it then it is fast enough, why would you want to watch a show faster? Yes for other things you might want the speed but will saving 30 seconds or a minute even on read and write times be worth having a 10 drive set up that is bulky and hard to maintain for the average user. And what if the time you save is only a couple of seconds would anybody even notice?
My goof off computer has 4 drives in RAID (well right now it is in pieces, it is my computer to toy around with, I've got 4 computers right now, two for playing with network stuff and one for taking apart and goofing with hardware stuff and one to use everyday). RAID is not something for the average "I bought my computer at Wal Mart" crowd.