Hi Butterfingers,
My DS211j and a Hitachi Deskstar 2TB 5k3000 drive arrived today. If you look elsewhere in the forums it seems other users have got these drives working successfully in their units. However, the drives have been accused of having a high failure rate (earning the nickname 'Deathstar'

) and unfortunately mine was one.
It powered up first time in the unit with no problems. I powered the 211j down safely, powered it up again and just got continuous clicking. Powered it on and off several times and then opened the unit up, changed the bay, same problem. Unfortunately I don't have a desktop unit or SATA connector unit to test the drive separately with on my network, so couldn't check if it was a problem with the DS211j itself, but the noise and perception from other users would say that that probably isn't where the fault lies. I was careful not to touch any PCBs on the hard drive and earthed myself, so it seems I was unlucky.
The drive had a batch date of JAN 2011 on it, some people have reported that there was a bit of a bad batch going round between DEC 2010 and FEB 2011, so that would concur, however, other people have had success. Additionally, the drive was sold as bare, thus only packed loosely in an anti static moisture bag and thin bubblewrap within the same parcel that contained my NAS, so it may have incurred damage in transit.
Just wanted to let you know if you do proceed, basically YMMV. As for me, I ordered the same model from another supplier (hoping to avoid the bad batch problem!) before the 211j and failed drive arrived, so I'll update you when I receive it and set my DS211j up.
Here's the Google Products review link:
http://bit.ly/iw7cLdKind Regards and Good Luck!