What's the largest USB HDD possible?

I know there used to be a 2tb limit which has now been fixed, but what’s the largest external USB HDD I can use with my WDTV LIVE?

I’ve found this at 6TB:

http://www.newegg.com/Product/Product.aspx?Item=N82E16822165287

But it looks like 2 x 3TBs, so I don’t know if that would work.  Even if it showed as 1 x 3TB could the WD handle it?

Anyone?

Steve W

Sorry, this is maybe more appropriate:

http://www.amazon.co.uk/Western-Digital-Studio-External-Drive/dp/B004QBOQ2M/ref=sr_1_1?ie=UTF8&qid=1316958926&sr=8-1

Would the WD see this as 1 x 6TB?

If so, if I had two of these (one for each of the 2 USB ports) would the WD TV LIVE handle all that data (12TB)?

Steve W