Although I have rated this dock as excellent in the past, I have awarded only one star (the minimum) for its failure to interface correctly to a WD Green 3TB SATA drive.
Amazon does not state that there is a maximum capacity for full utilisation of the disk. A 3TB drive installed in this dock shows up as just over 800GB only, whereas a 2TB drive shows the full 2TB.
Owing to the failure to see a 3TB drive correctly, I checked the technical specifications on the StarTech website only to find that it quotes 'tested to 2TB'. It does not record that it will not work for a 3TB drive.
Searching the Internet I have discovered that the limitation of external enclosures and docks to see a full 3TB is not unusual in early 2012. Only a few designers of such docks have overcome the limitation: apparently Sharkoon Technologies GmbH have a dock that will handle drives up to 3TB. It is called the QuickPort Combo, though Amazon does not yet state the 3TB limit (rather than 2TB) for that unit either.