I bought the RSC version and it seems like it only needed the 60 GB but I honestly don't know the ins and outs of HDDs so if it's still using that other 60 GB in reserve somehow I have no idea
The second 60GB he refers to is the unlocking. Which is basically de-encrypting it. Basically needs the other 60GB to move files than when all said and done..the other 60GB goes away.