Hi Carl,
I think we all knew that there wasn't any reason why the TwinStore couldn't use 2TB drives, in place of the 1TB drives recommended by Meridian.
However, there are definite reasons why for example, most pre 2011 Desktops cannot support 3TB drives without extra interface hardware and drivers.
Essentially, 2^32 by 512byte Sectors supported by most apps = 2.2Tb approx... and as most apps can't suport larger sectors, you're stuck.
The workarounds are UEFI interface on 2011 motherboards... or Host Bus Adaptors from the Disk Manufacturer.
So, if you are going order a 3TB Drive, make sure it comes with an HBA from that manufacturer.
FWIW, Meridian are using the Busybox Linux tools on the Ensemble and TwinStore and if it's properly configured, then it may work without an HBA.
However, I think your CORE is the XP based C15, so I'm not sure how that might react with the limitations mentioned above.