So for 3 nights I have attempted to clone my old 512 GB hd to a new 1TB Seagate SSHD hybrid drive and for 3 night I have failed. I keep finding that it randomly disconnects with the “Drive incorrectly removed” message from OSX.
I have deactivated all the autolog out/shutdown setting but still getting this issue and its driving me crazy.
Ajb2k3's Weblog 
How are you doing it (i.e., what’s the command that you’re using)?
Using Superduper via a pny usb3 adapter.
Going to try a different adapter over the weekend to see if thats the problem.