Been looking for these for ages. DCL sell through amazon, but if you buy a few it's a lot cheaper from their own website, as the postage is combined.
I ordered 5 of these for my new Microserver on Friday and received them Monday, packaged individually in plastic hard drive box things, all slotted into a big polystyrene hard drive holder box. I don't know of any other company that spends so much on packaging, so expect your hard drives to arrive safely.
The drives come with the 3 year Samsung warranty (I emailed DCL first) and all of mine have a manufacture date of 2011-05, although I flashed the firmware anyway to be on the safe side (it's not difficult).
The 5 that I ordered came to just about £270, including postage, which is the cheapest I could find, and I looked for a long while. That made it a lot cheaper than amazon, and about £5 cheaper than overclock. I'm not sure what the postage is like for a single drive, but there is definitely a saving here for those who want a few.
Hope this helps you in your quest for storage. DCL seem to be pretty good, though I hadn't heard of them until now.
I feel I should mention that every drive sounds different when it spins up on power on; I'm not quite sure how Samsung achieved this, but I think it sounds like something out of Halo, kinda like the Reach Edition 360 with the Halo startup sounds. Every drive makes noise starting up. At least this is cool :D
Oh and one more thing, I couldn't get their site to load on Firefox (using Mac OSX) so I used Safari and all was fine. Not sure if this is a fault on my end or theirs though.
EDIT: See here for a guide on the firmware update:http://forums.whirlpool.net.au/archive/1597038