I just bought a 3TB drive to replace a 1TB drive that's getting close to capacity. Both are internal sled drives and I so I formatted the new disc and just selected all the folders in the old drive and dragged them to the new drive. It says "about 3 hours" left. I'm wondering if that time estimate is a matter of the sheer volume being copied or if it's faster to use a cloning app like CCC or File Synchronization... i.e. if 3rd party applications copy in a different, smarter, faster way?